21156853793129 has 8 divisors (see below), whose sum is σ = 22275210735840. Its totient is φ = 20038980682656.

The previous prime is 21156853793123. The next prime is 21156853793161. The reversal of 21156853793129 is 92139735865112.

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

It is not a de Polignac number, because 21156853793129 - 2³² = 21152558825833 is a prime.

It is a super-2 number, since 2×21156853793129² (a number of 27 digits) contains 22 as substring.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (21156853793123) 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, 120868292 + ... + 121043205.

It is an arithmetic number, because the mean of its divisors is an integer number (2784401341980).

Almost surely, 2^{21156853793129} is an apocalyptic number.

It is an amenable number.

21156853793129 is a deficient number, since it is larger than the sum of its proper divisors (1118356942711).

21156853793129 is a wasteful number, since it uses less digits than its factorization.

21156853793129 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 241916119.

The product of its digits is 24494400, while the sum is 62.

The spelling of 21156853793129 in words is "twenty-one trillion, one hundred fifty-six billion, eight hundred fifty-three million, seven hundred ninety-three thousand, one hundred twenty-nine".