20642154156 has 72 divisors (see below), whose sum is σ = 57950082960. Its totient is φ = 6351426432.

The previous prime is 20642154139. The next prime is 20642154167. The reversal of 20642154156 is 65145124602.

20642154156 is a `hidden beast` number, since 2 + 0 + 64 + 2 + 1 + 541 + 56 = 666.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a self number, because there is not a number n which added to its sum of digits gives 20642154156.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 547225 + ... + 583728.

Almost surely, 2^20642154156 is an apocalyptic number.

20642154156 is a gapful number since it is divisible by the number (26) formed by its first and last digit.

It is an amenable number.

20642154156 is an abundant number, since it is smaller than the sum of its proper divisors (37307928804).

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

20642154156 is a wasteful number, since it uses less digits than its factorization.

20642154156 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1130992 (or 1130971 counting only the distinct ones).

The product of its (nonzero) digits is 57600, while the sum is 36.

Adding to 20642154156 its reverse (65145124602), we get a palindrome (85787278758).

The spelling of 20642154156 in words is "twenty billion, six hundred forty-two million, one hundred fifty-four thousand, one hundred fifty-six".