20718947844 has 36 divisors (see below), whose sum is σ = 59854738944. Its totient is φ = 5919699312.

The previous prime is 20718947827. The next prime is 20718947849. The reversal of 20718947844 is 44874981702.

20718947844 is a `hidden beast` number, since 20 + 71 + 89 + 478 + 4 + 4 = 666.

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 (20718947849) 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, 41108772 + ... + 41109275.

Almost surely, 2^20718947844 is an apocalyptic number.

It is an amenable number.

20718947844 is an abundant number, since it is smaller than the sum of its proper divisors (39135791100).

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

20718947844 is a wasteful number, since it uses less digits than its factorization.

20718947844 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 82218064 (or 82218059 counting only the distinct ones).

The product of its (nonzero) digits is 3612672, while the sum is 54.

The spelling of 20718947844 in words is "twenty billion, seven hundred eighteen million, nine hundred forty-seven thousand, eight hundred forty-four".