6420336129 has 45 divisors (see below), whose sum is σ = 9965456787. Its totient is φ = 4119168816.

The previous prime is 6420336121. The next prime is 6420336137. The reversal of 6420336129 is 9216330246.

The square root of 6420336129 is 80127.

It is a perfect power (a square), and thus also a powerful number.

6420336129 is a `hidden beast` number, since 6 + 4 + 2 + 0 + 33 + 612 + 9 = 666.

It is an interprime number because it is at equal distance from previous prime (6420336121) and next prime (6420336137).

It can be written as a sum of positive squares in only one way, i.e., 3366668529 + 3053667600 = 58023^2 + 55260^2 .

It is not a de Polignac number, because 6420336129 - 2³ = 6420336121 is a prime.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 6420336093 and 6420336102.

It is not an unprimeable number, because it can be changed into a prime (6420336121) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 44 ways as a sum of consecutive naturals, for example, 20912994 + ... + 20913300.

Almost surely, 2^6420336129 is an apocalyptic number.

6420336129 is the 80127-th square number.

6420336129 is the 40064-th centered octagonal number.

It is an amenable number.

6420336129 is a deficient number, since it is larger than the sum of its proper divisors (3545120658).

6420336129 is an frugal number, since it uses more digits than its factorization.

6420336129 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 684 (or 339 counting only the distinct ones).

The product of its (nonzero) digits is 46656, while the sum is 36.

The cubic root of 6420336129 is about 1858.5999531943.

Multiplying 6420336129 by its sum of digits (36), we get a square (231132100644 = 480762²).

Multiplying 6420336129 by its product of nonzero digits (46656), we get a square (299547202434624 = 17307432²).

The spelling of 6420336129 in words is "six billion, four hundred twenty million, three hundred thirty-six thousand, one hundred twenty-nine".