20551505634 has 36 divisors (see below), whose sum is σ = 48944293398. Its totient is φ = 6227728320.

The previous prime is 20551505599. The next prime is 20551505677. The reversal of 20551505634 is 43650515502.

20551505634 is a `hidden beast` number, since 2 + 0 + 5 + 5 + 15 + 0 + 5 + 634 = 666.

It can be written as a sum of positive squares in only one way, i.e., 16217258409 + 4334247225 = 127347^2 + 65835^2 .

It is an unprimeable number.

It is a polite number, since it can be written in 17 ways as a sum of consecutive naturals, for example, 4715799 + ... + 4720154.

Almost surely, 2^20551505634 is an apocalyptic number.

20551505634 is an abundant number, since it is smaller than the sum of its proper divisors (28392787764).

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

20551505634 is a wasteful number, since it uses less digits than its factorization.

20551505634 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9435983 (or 9435969 counting only the distinct ones).

The product of its (nonzero) digits is 90000, while the sum is 36.

The spelling of 20551505634 in words is "twenty billion, five hundred fifty-one million, five hundred five thousand, six hundred thirty-four".