21010113231 has 4 divisors (see below), whose sum is σ = 28013484312. Its totient is φ = 14006742152.

The previous prime is 21010113211. The next prime is 21010113247. The reversal of 21010113231 is 13231101012.

It is a happy number.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 21010113231 - 2²⁹ = 20473242319 is a prime.

It is a super-2 number, since 2×21010113231² (a number of 21 digits) contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 21010113231.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21010113211) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3501685536 + ... + 3501685541.

It is an arithmetic number, because the mean of its divisors is an integer number (7003371078).

Almost surely, 2^21010113231 is an apocalyptic number.

21010113231 is a deficient number, since it is larger than the sum of its proper divisors (7003371081).

21010113231 is an equidigital number, since it uses as much as digits as its factorization.

21010113231 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7003371080.

The product of its (nonzero) digits is 36, while the sum is 15.

Adding to 21010113231 its reverse (13231101012), we get a palindrome (34241214243).

The spelling of 21010113231 in words is "twenty-one billion, ten million, one hundred thirteen thousand, two hundred thirty-one".