21211200231 has 32 divisors (see below), whose sum is σ = 31837757952. Its totient is φ = 12463355520.

The previous prime is 21211200211. The next prime is 21211200233. The reversal of 21211200231 is 13200211212.

It is not a de Polignac number, because 21211200231 - 2²¹ = 21209103079 is a prime.

It is a super-2 number, since 2×21211200231² (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 21211200231.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21211200233) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 491481 + ... + 532893.

It is an arithmetic number, because the mean of its divisors is an integer number (994929936).

Almost surely, 2^21211200231 is an apocalyptic number.

21211200231 is a deficient number, since it is larger than the sum of its proper divisors (10626557721).

21211200231 is a wasteful number, since it uses less digits than its factorization.

21211200231 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 42023.

The product of its (nonzero) digits is 48, while the sum is 15.

Adding to 21211200231 its reverse (13200211212), we get a palindrome (34411411443).

The spelling of 21211200231 in words is "twenty-one billion, two hundred eleven million, two hundred thousand, two hundred thirty-one".