21621890585863 has 8 divisors (see below), whose sum is σ = 21667952195136. Its totient is φ = 21575872332000.

The previous prime is 21621890585831. The next prime is 21621890585881. The reversal of 21621890585863 is 36858509812612.

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 21621890585863 - 2⁵ = 21621890585831 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21621890585795 and 21621890585804.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21621890525863) 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, 9840268 + ... + 11835313.

It is an arithmetic number, because the mean of its divisors is an integer number (2708494024392).

Almost surely, 2^{21621890585863} is an apocalyptic number.

21621890585863 is a deficient number, since it is larger than the sum of its proper divisors (46061609273).

21621890585863 is a wasteful number, since it uses less digits than its factorization.

21621890585863 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 21677705.

The product of its (nonzero) digits is 49766400, while the sum is 64.

The spelling of 21621890585863 in words is "twenty-one trillion, six hundred twenty-one billion, eight hundred ninety million, five hundred eighty-five thousand, eight hundred sixty-three".