25493021931 has 16 divisors (see below), whose sum is σ = 36653763104. Its totient is φ = 15667271424.

The previous prime is 25493021881. The next prime is 25493021933. The reversal of 25493021931 is 13912039452.

It is not a de Polignac number, because 25493021931 - 2¹¹ = 25493019883 is a prime.

It is a super-2 number, since 2×25493021931² (a number of 22 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (39).

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 25493021931.

It is not an unprimeable number, because it can be changed into a prime (25493021933) 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 15 ways as a sum of consecutive naturals, for example, 402226 + ... + 461271.

It is an arithmetic number, because the mean of its divisors is an integer number (2290860194).

Almost surely, 2^25493021931 is an apocalyptic number.

25493021931 is a deficient number, since it is larger than the sum of its proper divisors (11160741173).

25493021931 is a wasteful number, since it uses less digits than its factorization.

25493021931 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 864270.

The product of its (nonzero) digits is 58320, while the sum is 39.

The spelling of 25493021931 in words is "twenty-five billion, four hundred ninety-three million, twenty-one thousand, nine hundred thirty-one".