21252511503 has 18 divisors (see below), whose sum is σ = 32398801344. Its totient is φ = 13422636792.

The previous prime is 21252511471. The next prime is 21252511591. The reversal of 21252511503 is 30511525212.

21252511503 is a `hidden beast` number, since 2 + 125 + 25 + 11 + 503 = 666.

It is not a de Polignac number, because 21252511503 - 2⁵ = 21252511471 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21252511103) by changing a digit.

It is a polite number, since it can be written in 17 ways as a sum of consecutive naturals, for example, 3267375 + ... + 3273872.

It is an arithmetic number, because the mean of its divisors is an integer number (1799933408).

Almost surely, 2^21252511503 is an apocalyptic number.

21252511503 is a deficient number, since it is larger than the sum of its proper divisors (11146289841).

21252511503 is a wasteful number, since it uses less digits than its factorization.

21252511503 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6541291 (or 6541269 counting only the distinct ones).

The product of its (nonzero) digits is 3000, while the sum is 27.

The spelling of 21252511503 in words is "twenty-one billion, two hundred fifty-two million, five hundred eleven thousand, five hundred three".