21129572611 has 16 divisors (see below), whose sum is σ = 25429384960. Its totient is φ = 17150862240.

The previous prime is 21129572567. The next prime is 21129572617. The reversal of 21129572611 is 11627592112.

It is not a de Polignac number, because 21129572611 - 2¹⁵ = 21129539843 is a prime.

It is not an unprimeable number, because it can be changed into a prime (21129572617) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 309016 + ... + 371146.

It is an arithmetic number, because the mean of its divisors is an integer number (1589336560).

Almost surely, 2^21129572611 is an apocalyptic number.

21129572611 is a deficient number, since it is larger than the sum of its proper divisors (4299812349).

21129572611 is a wasteful number, since it uses less digits than its factorization.

21129572611 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 64714.

The product of its digits is 15120, while the sum is 37.

The spelling of 21129572611 in words is "twenty-one billion, one hundred twenty-nine million, five hundred seventy-two thousand, six hundred eleven".