21295897623 has 256 divisors, whose sum is σ = 45106790400. Its totient is φ = 9562613760.

The previous prime is 21295897621. The next prime is 21295897627. The reversal of 21295897623 is 32679859212.

21295897623 is a `hidden beast` number, since 2 + 1 + 2 + 9 + 5 + 8 + 9 + 7 + 623 = 666.

It is not a de Polignac number, because 21295897623 - 2¹ = 21295897621 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 21295897623.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21295897621) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 255 ways as a sum of consecutive naturals, for example, 58026786 + ... + 58027152.

It is an arithmetic number, because the mean of its divisors is an integer number (176198400).

Almost surely, 2^21295897623 is an apocalyptic number.

21295897623 is an abundant number, since it is smaller than the sum of its proper divisors (23810892777).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21295897623 is a wasteful number, since it uses less digits than its factorization.

21295897623 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 539 (or 533 counting only the distinct ones).

The product of its digits is 3265920, while the sum is 54.

The spelling of 21295897623 in words is "twenty-one billion, two hundred ninety-five million, eight hundred ninety-seven thousand, six hundred twenty-three".