21231204402291 has 16 divisors (see below), whose sum is σ = 30515343958176. Its totient is φ = 13052708557056.

The previous prime is 21231204402223. The next prime is 21231204402323. The reversal of 21231204402291 is 19220440213212.

It is not a de Polignac number, because 21231204402291 - 2¹¹ = 21231204400243 is a prime.

It is not an unprimeable number, because it can be changed into a prime (21231204402211) 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, 263459160 + ... + 263539733.

It is an arithmetic number, because the mean of its divisors is an integer number (1907208997386).

Almost surely, 2^{21231204402291} is an apocalyptic number.

21231204402291 is a deficient number, since it is larger than the sum of its proper divisors (9284139555885).

21231204402291 is a wasteful number, since it uses less digits than its factorization.

21231204402291 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 526999942.

The product of its (nonzero) digits is 13824, while the sum is 33.

The spelling of 21231204402291 in words is "twenty-one trillion, two hundred thirty-one billion, two hundred four million, four hundred two thousand, two hundred ninety-one".