20644136202 has 16 divisors (see below), whose sum is σ = 41290159680. Its totient is φ = 6881064192.

The previous prime is 20644136179. The next prime is 20644136209. The reversal of 20644136202 is 20263144602.

It is a self number, because there is not a number n which added to its sum of digits gives 20644136202.

It is not an unprimeable number, because it can be changed into a prime (20644136209) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 92074 + ... + 223082.

It is an arithmetic number, because the mean of its divisors is an integer number (2580634980).

Almost surely, 2^20644136202 is an apocalyptic number.

20644136202 is an abundant number, since it is smaller than the sum of its proper divisors (20646023478).

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

20644136202 is a wasteful number, since it uses less digits than its factorization.

20644136202 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 157277.

The product of its (nonzero) digits is 13824, while the sum is 30.

The spelling of 20644136202 in words is "twenty billion, six hundred forty-four million, one hundred thirty-six thousand, two hundred two".