20644840074 has 32 divisors (see below), whose sum is σ = 41389508160. Its totient is φ = 6864998400.

The previous prime is 20644840063. The next prime is 20644840093. The reversal of 20644840074 is 47004844602.

It is a Curzon number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 5401084 + ... + 5404904.

It is an arithmetic number, because the mean of its divisors is an integer number (1293422130).

Almost surely, 2^20644840074 is an apocalyptic number.

20644840074 is an abundant number, since it is smaller than the sum of its proper divisors (20744668086).

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

20644840074 is a wasteful number, since it uses less digits than its factorization.

20644840074 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5766.

The product of its (nonzero) digits is 172032, while the sum is 39.

The spelling of 20644840074 in words is "twenty billion, six hundred forty-four million, eight hundred forty thousand, seventy-four".