21316903425 has 72 divisors (see below), whose sum is σ = 39953552184. Its totient is φ = 10852807680.

The previous prime is 21316903423. The next prime is 21316903429. The reversal of 21316903425 is 52430961312.

21316903425 is a `hidden beast` number, since 213 + 16 + 9 + 0 + 3 + 425 = 666.

It can be written as a sum of positive squares in 12 ways, for example, as 1963641969 + 19353261456 = 44313^2 + 139116^2 .

It is not a de Polignac number, because 21316903425 - 2¹ = 21316903423 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 21316903425.

It is not an unprimeable number, because it can be changed into a prime (21316903423) by changing a digit.

It is a polite number, since it can be written in 71 ways as a sum of consecutive naturals, for example, 417069 + ... + 465381.

It is an arithmetic number, because the mean of its divisors is an integer number (554910447).

Almost surely, 2^21316903425 is an apocalyptic number.

21316903425 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

It is an amenable number.

21316903425 is a deficient number, since it is larger than the sum of its proper divisors (18636648759).

21316903425 is a wasteful number, since it uses less digits than its factorization.

21316903425 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 48419 (or 48411 counting only the distinct ones).

The product of its (nonzero) digits is 38880, while the sum is 36.

The spelling of 21316903425 in words is "twenty-one billion, three hundred sixteen million, nine hundred three thousand, four hundred twenty-five".