21023131201 has 4 divisors (see below), whose sum is σ = 21024272304. Its totient is φ = 21021990100.

The previous prime is 21023131189. The next prime is 21023131231. The reversal of 21023131201 is 10213132012.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21023131201 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21023131231) 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, 542455 + ... + 579916.

It is an arithmetic number, because the mean of its divisors is an integer number (5256068076).

Almost surely, 2^21023131201 is an apocalyptic number.

It is an amenable number.

21023131201 is a deficient number, since it is larger than the sum of its proper divisors (1141103).

21023131201 is a wasteful number, since it uses less digits than its factorization.

21023131201 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1141102.

The product of its (nonzero) digits is 72, while the sum is 16.

Adding to 21023131201 its reverse (10213132012), we get a palindrome (31236263213).

The spelling of 21023131201 in words is "twenty-one billion, twenty-three million, one hundred thirty-one thousand, two hundred one".