21200231244 has 24 divisors (see below), whose sum is σ = 49517556480. Its totient is φ = 7059550864.

The previous prime is 21200231233. The next prime is 21200231249. The reversal of 21200231244 is 44213200212.

It is a self number, because there is not a number n which added to its sum of digits gives 21200231244.

It is not an unprimeable number, because it can be changed into a prime (21200231249) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 886824 + ... + 910415.

It is an arithmetic number, because the mean of its divisors is an integer number (2063231520).

Almost surely, 2^21200231244 is an apocalyptic number.

It is an amenable number.

21200231244 is an abundant number, since it is smaller than the sum of its proper divisors (28317325236).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21200231244 is a wasteful number, since it uses less digits than its factorization.

21200231244 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1798229 (or 1798227 counting only the distinct ones).

The product of its (nonzero) digits is 768, while the sum is 21.

Adding to 21200231244 its reverse (44213200212), we get a palindrome (65413431456).

The spelling of 21200231244 in words is "twenty-one billion, two hundred million, two hundred thirty-one thousand, two hundred forty-four".