21456593431 has 16 divisors (see below), whose sum is σ = 26417036800. Its totient is φ = 16970910048.

The previous prime is 21456593383. The next prime is 21456593443. The reversal of 21456593431 is 13439565412.

It is a cyclic number.

It is not a de Polignac number, because 21456593431 - 2²¹ = 21454496279 is a prime.

It is a super-2 number, since 2×21456593431² (a number of 21 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21456593531) 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, 241900 + ... + 318478.

It is an arithmetic number, because the mean of its divisors is an integer number (1651064800).

Almost surely, 2^21456593431 is an apocalyptic number.

21456593431 is a deficient number, since it is larger than the sum of its proper divisors (4960443369).

21456593431 is a wasteful number, since it uses less digits than its factorization.

21456593431 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 79678.

The product of its digits is 388800, while the sum is 43.

The spelling of 21456593431 in words is "twenty-one billion, four hundred fifty-six million, five hundred ninety-three thousand, four hundred thirty-one".