21049166831 has 32 divisors (see below), whose sum is σ = 27166164480. Its totient is φ = 15825801600.

The previous prime is 21049166807. The next prime is 21049166839. The reversal of 21049166831 is 13866194012.

It is not a de Polignac number, because 21049166831 - 2³⁴ = 3869297647 is a prime.

It is a super-2 number, since 2×21049166831² (a number of 21 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21049166839) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 5506901 + ... + 5510721.

It is an arithmetic number, because the mean of its divisors is an integer number (848942640).

Almost surely, 2^21049166831 is an apocalyptic number.

21049166831 is a deficient number, since it is larger than the sum of its proper divisors (6116997649).

21049166831 is a wasteful number, since it uses less digits than its factorization.

21049166831 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6335.

The product of its (nonzero) digits is 62208, while the sum is 41.

The spelling of 21049166831 in words is "twenty-one billion, forty-nine million, one hundred sixty-six thousand, eight hundred thirty-one".