21202103231 has 24 divisors (see below), whose sum is σ = 22877640000. Its totient is φ = 19642456064.

The previous prime is 21202103227. The next prime is 21202103257. The reversal of 21202103231 is 13230120212.

It is not a de Polignac number, because 21202103231 - 2² = 21202103227 is a prime.

It is a super-2 number, since 2×21202103231² (a number of 21 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (17).

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21202103291) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 6145595 + ... + 6149043.

It is an arithmetic number, because the mean of its divisors is an integer number (953235000).

Almost surely, 2^21202103231 is an apocalyptic number.

21202103231 is a deficient number, since it is larger than the sum of its proper divisors (1675536769).

21202103231 is a wasteful number, since it uses less digits than its factorization.

21202103231 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3811 (or 3794 counting only the distinct ones).

The product of its (nonzero) digits is 144, while the sum is 17.

Adding to 21202103231 its reverse (13230120212), we get a palindrome (34432223443).

The spelling of 21202103231 in words is "twenty-one billion, two hundred two million, one hundred three thousand, two hundred thirty-one".