21841800724 has 12 divisors (see below), whose sum is σ = 38232601204. Its totient is φ = 10918200384.

The previous prime is 21841800709. The next prime is 21841800733. The reversal of 21841800724 is 42700814812.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 10588410000 + 11253390724 = 102900^2 + 106082^2 .

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 656739 + ... + 689194.

Almost surely, 2^21841800724 is an apocalyptic number.

It is an amenable number.

21841800724 is a deficient number, since it is larger than the sum of its proper divisors (16390800480).

21841800724 is a wasteful number, since it uses less digits than its factorization.

21841800724 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1349994 (or 1349992 counting only the distinct ones).

The product of its (nonzero) digits is 28672, while the sum is 37.

The spelling of 21841800724 in words is "twenty-one billion, eight hundred forty-one million, eight hundred thousand, seven hundred twenty-four".