21955777344 has 84 divisors (see below), whose sum is σ = 62965250244. Its totient is φ = 7314757632.

The previous prime is 21955777331. The next prime is 21955777357. The reversal of 21955777344 is 44377755912.

21955777344 is a `hidden beast` number, since 2 + 19 + 557 + 7 + 73 + 4 + 4 = 666.

It is an interprime number because it is at equal distance from previous prime (21955777331) and next prime (21955777357).

It can be written as a sum of positive squares in 2 ways, for example, as 9041727744 + 12914049600 = 95088^2 + 113640^2 .

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 1221994 + ... + 1239830.

Almost surely, 2^21955777344 is an apocalyptic number.

21955777344 is a gapful number since it is divisible by the number (24) formed by its first and last digit.

It is an amenable number.

21955777344 is an abundant number, since it is smaller than the sum of its proper divisors (41009472900).

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

21955777344 is a wasteful number, since it uses less digits than its factorization.

21955777344 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 19992 (or 19979 counting only the distinct ones).

The product of its digits is 7408800, while the sum is 54.

The spelling of 21955777344 in words is "twenty-one billion, nine hundred fifty-five million, seven hundred seventy-seven thousand, three hundred forty-four".