21656091589463 has 8 divisors (see below), whose sum is σ = 22473524839680. Its totient is φ = 20843369770720.

The previous prime is 21656091589387. The next prime is 21656091589519. The reversal of 21656091589463 is 36498519065612.

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 21656091589463 - 2⁸ = 21656091589207 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 21656091589463.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21656091589763) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1177848503 + ... + 1177866888.

It is an arithmetic number, because the mean of its divisors is an integer number (2809190604960).

Almost surely, 2^{21656091589463} is an apocalyptic number.

21656091589463 is a deficient number, since it is larger than the sum of its proper divisors (817433250217).

21656091589463 is a wasteful number, since it uses less digits than its factorization.

21656091589463 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2355715737.

The product of its (nonzero) digits is 83980800, while the sum is 65.

The spelling of 21656091589463 in words is "twenty-one trillion, six hundred fifty-six billion, ninety-one million, five hundred eighty-nine thousand, four hundred sixty-three".