21590918847 has 32 divisors (see below), whose sum is σ = 33221664000. Its totient is φ = 13842108000.

The previous prime is 21590918759. The next prime is 21590918849. The reversal of 21590918847 is 74881909512.

It is a happy number.

21590918847 is a `hidden beast` number, since 2 + 1 + 590 + 9 + 1 + 8 + 8 + 47 = 666.

It is not a de Polignac number, because 21590918847 - 2¹⁶ = 21590853311 is a prime.

It is a hoax number, since the sum of its digits (54) coincides with the sum of the digits of its distinct prime factors.

It is a junction number, because it is equal to n+sod(n) for n = 21590918793 and 21590918802.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21590918849) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 141604 + ... + 251462.

It is an arithmetic number, because the mean of its divisors is an integer number (1038177000).

Almost surely, 2^21590918847 is an apocalyptic number.

21590918847 is a gapful number since it is divisible by the number (27) formed by its first and last digit.

21590918847 is a deficient number, since it is larger than the sum of its proper divisors (11630745153).

21590918847 is a wasteful number, since it uses less digits than its factorization.

21590918847 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 110148 (or 110142 counting only the distinct ones).

The product of its (nonzero) digits is 1451520, while the sum is 54.

The spelling of 21590918847 in words is "twenty-one billion, five hundred ninety million, nine hundred eighteen thousand, eight hundred forty-seven".