21647747434212 has 36 divisors (see below), whose sum is σ = 55262483970876. Its totient is φ = 7144471099200.

The previous prime is 21647747434189. The next prime is 21647747434213. The reversal of 21647747434212 is 21243474774612.

21647747434212 is a `hidden beast` number, since 2 + 1 + 64 + 77 + 474 + 3 + 42 + 1 + 2 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 18669865706496 + 2977881727716 = 4320864^2 + 1725654^2 .

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

It is not an unprimeable number, because it can be changed into a prime (21647747434213) 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, 2976859323 + ... + 2976866594.

It is an arithmetic number, because the mean of its divisors is an integer number (1535068999191).

Almost surely, 2^{21647747434212} is an apocalyptic number.

It is an amenable number.

21647747434212 is an abundant number, since it is smaller than the sum of its proper divisors (33614736536664).

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

21647747434212 is a wasteful number, since it uses less digits than its factorization.

21647747434212 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5953726028 (or 5953726023 counting only the distinct ones).

The product of its digits is 12644352, while the sum is 54.

The spelling of 21647747434212 in words is "twenty-one trillion, six hundred forty-seven billion, seven hundred forty-seven million, four hundred thirty-four thousand, two hundred twelve".