21779331156 has 36 divisors (see below), whose sum is σ = 60058156704. Its totient is φ = 6599797200.

The previous prime is 21779331137. The next prime is 21779331173. The reversal of 21779331156 is 65113397712.

21779331156 is a `hidden beast` number, since 217 + 79 + 3 + 311 + 56 = 666.

It is a tau number, because it is divible by the number of its divisors (36).

It is a super-3 number, since 3×21779331156³ (a number of 32 digits) contains 333 as substring.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 27498760 + ... + 27499551.

Almost surely, 2^21779331156 is an apocalyptic number.

It is an amenable number.

21779331156 is an abundant number, since it is smaller than the sum of its proper divisors (38278825548).

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

21779331156 is a wasteful number, since it uses less digits than its factorization.

21779331156 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 54998332 (or 54998327 counting only the distinct ones).

The product of its digits is 238140, while the sum is 45.

The spelling of 21779331156 in words is "twenty-one billion, seven hundred seventy-nine million, three hundred thirty-one thousand, one hundred fifty-six".