21861574224 has 80 divisors (see below), whose sum is σ = 65860963200. Its totient is φ = 6246159360.

The previous prime is 21861574199. The next prime is 21861574271. The reversal of 21861574224 is 42247516812.

It is a super-2 number, since 2×21861574224² (a number of 21 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (42).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 647457 + ... + 680384.

It is an arithmetic number, because the mean of its divisors is an integer number (823262040).

Almost surely, 2^21861574224 is an apocalyptic number.

21861574224 is a gapful number since it is divisible by the number (24) formed by its first and last digit.

It is an amenable number.

21861574224 is an abundant number, since it is smaller than the sum of its proper divisors (43999388976).

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

21861574224 is a wasteful number, since it uses less digits than its factorization.

21861574224 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1327873 (or 1327853 counting only the distinct ones).

The product of its digits is 215040, while the sum is 42.

The spelling of 21861574224 in words is "twenty-one billion, eight hundred sixty-one million, five hundred seventy-four thousand, two hundred twenty-four".