20415694567129 has 27 divisors (see below), whose sum is σ = 21500726024127. Its totient is φ = 19383820170000.

The previous prime is 20415694567111. The next prime is 20415694567199. The reversal of 20415694567129 is 92176549651402.

The square root of 20415694567129 is 4518373.

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

It can be written as a sum of positive squares in only one way, i.e., 31372557129 + 20384322010000 = 177123^2 + 4514900^2 .

It is a de Polignac number, because none of the positive numbers 2^k-20415694567129 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20415694567199) 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 26 ways as a sum of consecutive naturals, for example, 15692308779 + ... + 15692310079.

Almost surely, 2^{20415694567129} is an apocalyptic number.

20415694567129 is the 4518373-rd square number.

20415694567129 is the 2259187-th centered octagonal number.

It is an amenable number.

20415694567129 is a deficient number, since it is larger than the sum of its proper divisors (1085031456998).

20415694567129 is an frugal number, since it uses more digits than its factorization.

20415694567129 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2950 (or 1475 counting only the distinct ones).

The product of its (nonzero) digits is 32659200, while the sum is 61.

The spelling of 20415694567129 in words is "twenty trillion, four hundred fifteen billion, six hundred ninety-four million, five hundred sixty-seven thousand, one hundred twenty-nine".