21656251635063 has 16 divisors (see below), whose sum is σ = 28928295472896. Its totient is φ = 14410855368000.

The previous prime is 21656251634999. The next prime is 21656251635143. The reversal of 21656251635063 is 36053615265612.

It is not a de Polignac number, because 21656251635063 - 2⁶ = 21656251634999 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 21656251634997 and 21656251635015.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21656251635163) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 173474995 + ... + 173599787.

It is an arithmetic number, because the mean of its divisors is an integer number (1808018467056).

Almost surely, 2^{21656251635063} is an apocalyptic number.

21656251635063 is a deficient number, since it is larger than the sum of its proper divisors (7272043837833).

21656251635063 is a wasteful number, since it uses less digits than its factorization.

21656251635063 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 231094.

The product of its (nonzero) digits is 5832000, while the sum is 51.

The spelling of 21656251635063 in words is "twenty-one trillion, six hundred fifty-six billion, two hundred fifty-one million, six hundred thirty-five thousand, sixty-three".