21525507371 has 8 divisors (see below), whose sum is σ = 21726088560. Its totient is φ = 21324982752.

The previous prime is 21525507331. The next prime is 21525507391. The reversal of 21525507371 is 17370552512.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 21525507371 - 2⁶ = 21525507307 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21525507331) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1419596 + ... + 1434678.

It is an arithmetic number, because the mean of its divisors is an integer number (2715761070).

Almost surely, 2^21525507371 is an apocalyptic number.

21525507371 is a deficient number, since it is larger than the sum of its proper divisors (200581189).

21525507371 is a wasteful number, since it uses less digits than its factorization.

21525507371 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 28285.

The product of its (nonzero) digits is 73500, while the sum is 38.

The spelling of 21525507371 in words is "twenty-one billion, five hundred twenty-five million, five hundred seven thousand, three hundred seventy-one".