21311310033231 has 128 divisors (see below), whose sum is σ = 32379532738560. Its totient is φ = 12393645158400.

The previous prime is 21311310033203. The next prime is 21311310033257. The reversal of 21311310033231 is 13233001311312.

It is not a de Polignac number, because 21311310033231 - 2⁵ = 21311310033199 is a prime.

It is a super-2 number, since 2×21311310033231² (a number of 27 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21311310033331) by changing a digit.

It is a polite number, since it can be written in 127 ways as a sum of consecutive naturals, for example, 7559881540 + ... + 7559884358.

It is an arithmetic number, because the mean of its divisors is an integer number (252965099520).

Almost surely, 2^{21311310033231} is an apocalyptic number.

21311310033231 is a deficient number, since it is larger than the sum of its proper divisors (11068222705329).

21311310033231 is a wasteful number, since it uses less digits than its factorization.

21311310033231 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3917.

The product of its (nonzero) digits is 972, while the sum is 24.

Adding to 21311310033231 its reverse (13233001311312), we get a palindrome (34544311344543).

The spelling of 21311310033231 in words is "twenty-one trillion, three hundred eleven billion, three hundred ten million, thirty-three thousand, two hundred thirty-one".