21931792308036 has 144 divisors (see below), whose sum is σ = 59789423193136. Its totient is φ = 6738503933952.

The previous prime is 21931792308031. The next prime is 21931792308043. The reversal of 21931792308036 is 63080329713912.

21931792308036 is a `hidden beast` number, since 2 + 19 + 317 + 9 + 2 + 308 + 0 + 3 + 6 = 666.

It can be written as a sum of positive squares in 8 ways, for example, as 14066325260100 + 7865467047936 = 3750510^2 + 2804544^2 .

It is not an unprimeable number, because it can be changed into a prime (21931792308031) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 2663884176 + ... + 2663892408.

Almost surely, 2^{21931792308036} is an apocalyptic number.

21931792308036 is a gapful number since it is divisible by the number (26) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21931792308036, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (29894711596568).

21931792308036 is an abundant number, since it is smaller than the sum of its proper divisors (37857630885100).

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

21931792308036 is a wasteful number, since it uses less digits than its factorization.

21931792308036 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 15782 (or 15777 counting only the distinct ones).

The product of its (nonzero) digits is 2939328, while the sum is 54.

The spelling of 21931792308036 in words is "twenty-one trillion, nine hundred thirty-one billion, seven hundred ninety-two million, three hundred eight thousand, thirty-six".