21011685129 has 24 divisors (see below), whose sum is σ = 30850747200. Its totient is φ = 13778602272.

The previous prime is 21011685113. The next prime is 21011685181. The reversal of 21011685129 is 92158611012.

21011685129 is a `hidden beast` number, since 21 + 0 + 116 + 8 + 512 + 9 = 666.

It is not a de Polignac number, because 21011685129 - 2⁴ = 21011685113 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 21011685093 and 21011685102.

It is not an unprimeable number, because it can be changed into a prime (21011685199) 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 23 ways as a sum of consecutive naturals, for example, 62062 + ... + 214184.

It is an arithmetic number, because the mean of its divisors is an integer number (1285447800).

Almost surely, 2^21011685129 is an apocalyptic number.

It is an amenable number.

21011685129 is a deficient number, since it is larger than the sum of its proper divisors (9839062071).

21011685129 is a wasteful number, since it uses less digits than its factorization.

21011685129 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 152381 (or 152378 counting only the distinct ones).

The product of its (nonzero) digits is 8640, while the sum is 36.

The spelling of 21011685129 in words is "twenty-one billion, eleven million, six hundred eighty-five thousand, one hundred twenty-nine".