21121010231 has 12 divisors (see below), whose sum is σ = 22057280856. Its totient is φ = 20216988480.

The previous prime is 21121010221. The next prime is 21121010269. The reversal of 21121010231 is 13201012112.

It is not a de Polignac number, because 21121010231 - 2⁶ = 21121010167 is a prime.

It is a super-2 number, since 2×21121010231² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21121010221) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 29441 + ... + 207626.

It is an arithmetic number, because the mean of its divisors is an integer number (1838106738).

Almost surely, 2^21121010231 is an apocalyptic number.

21121010231 is a deficient number, since it is larger than the sum of its proper divisors (936270625).

21121010231 is an equidigital number, since it uses as much as digits as its factorization.

21121010231 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 237202 (or 237161 counting only the distinct ones).

The product of its (nonzero) digits is 24, while the sum is 14.

Adding to 21121010231 its reverse (13201012112), we get a palindrome (34322022343).

The spelling of 21121010231 in words is "twenty-one billion, one hundred twenty-one million, ten thousand, two hundred thirty-one".