21506731356312 has 24 divisors (see below), whose sum is σ = 58247397423540. Its totient is φ = 7168910452080.

The previous prime is 21506731356307. The next prime is 21506731356343. The reversal of 21506731356312 is 21365313760512.

21506731356312 is a `hidden beast` number, since 2 + 1 + 5 + 0 + 6 + 7 + 3 + 1 + 3 + 5 + 631 + 2 = 666.

It is a tau number, because it is divible by the number of its divisors (24).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 149352301014 + ... + 149352301157.

Almost surely, 2^{21506731356312} is an apocalyptic number.

It is an amenable number.

21506731356312 is an abundant number, since it is smaller than the sum of its proper divisors (36740666067228).

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

21506731356312 is a wasteful number, since it uses less digits than its factorization.

21506731356312 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 298704602183 (or 298704602176 counting only the distinct ones).

The product of its (nonzero) digits is 680400, while the sum is 45.

The spelling of 21506731356312 in words is "twenty-one trillion, five hundred six billion, seven hundred thirty-one million, three hundred fifty-six thousand, three hundred twelve".