21525113131 has 8 divisors (see below), whose sum is σ = 21809813760. Its totient is φ = 21242267688.

The previous prime is 21525113123. The next prime is 21525113147. The reversal of 21525113131 is 13131152512.

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 21525113131 - 2³ = 21525113123 is a prime.

It is a super-2 number, since 2×21525113131² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21525113096 and 21525113105.

It is not an unprimeable number, because it can be changed into a prime (21525113111) 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, 440431 + ... + 486856.

It is an arithmetic number, because the mean of its divisors is an integer number (2726226720).

Almost surely, 2^21525113131 is an apocalyptic number.

21525113131 is a deficient number, since it is larger than the sum of its proper divisors (284700629).

21525113131 is a wasteful number, since it uses less digits than its factorization.

21525113131 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 927593.

The product of its digits is 900, while the sum is 25.

Adding to 21525113131 its reverse (13131152512), we get a palindrome (34656265643).

The spelling of 21525113131 in words is "twenty-one billion, five hundred twenty-five million, one hundred thirteen thousand, one hundred thirty-one".