21704739970842 has 24 divisors (see below), whose sum is σ = 47027347915860. Its totient is φ = 7234850044800.

The previous prime is 21704739970817. The next prime is 21704739970847. The reversal of 21704739970842 is 24807993740712.

21704739970842 is a `hidden beast` number, since 2 + 1 + 7 + 0 + 473 + 99 + 70 + 8 + 4 + 2 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 15583316800041 + 6121423170801 = 3947571^2 + 2474151^2 .

It is a self number, because there is not a number n which added to its sum of digits gives 21704739970842.

It is not an unprimeable number, because it can be changed into a prime (21704739970847) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 3134617 + ... + 7296252.

Almost surely, 2^{21704739970842} is an apocalyptic number.

21704739970842 is an abundant number, since it is smaller than the sum of its proper divisors (25322607945018).

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

21704739970842 is a wasteful number, since it uses less digits than its factorization.

21704739970842 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10546478 (or 10546475 counting only the distinct ones).

The product of its (nonzero) digits is 42674688, while the sum is 63.

The spelling of 21704739970842 in words is "twenty-one trillion, seven hundred four billion, seven hundred thirty-nine million, nine hundred seventy thousand, eight hundred forty-two".