6406553021 has 8 divisors (see below), whose sum is σ = 7028013600. Its totient is φ = 5791600240.

The previous prime is 6406552993. The next prime is 6406553029. The reversal of 6406553021 is 1203556046.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 6406553021 - 2²² = 6402358717 is a prime.

It is a super-2 number, since 2×6406553021² = 82087843221768452882, which contains 22 as substring.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (6406553029) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1624886 + ... + 1628823.

It is an arithmetic number, because the mean of its divisors is an integer number (878501700).

Almost surely, 2^6406553021 is an apocalyptic number.

It is an amenable number.

6406553021 is a deficient number, since it is larger than the sum of its proper divisors (621460579).

6406553021 is a wasteful number, since it uses less digits than its factorization.

6406553021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3253899.

The product of its (nonzero) digits is 21600, while the sum is 32.

The square root of 6406553021 is about 80040.9459027066. The cubic root of 6406553021 is about 1857.2689928988.

The spelling of 6406553021 in words is "six billion, four hundred six million, five hundred fifty-three thousand, twenty-one".