20351615556 has 24 divisors (see below), whose sum is σ = 47614424704. Its totient is φ = 6765683040.

The previous prime is 20351615539. The next prime is 20351615651. The reversal of 20351615556 is 65551615302.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2268940 + ... + 2277891.

Almost surely, 2^20351615556 is an apocalyptic number.

It is an amenable number.

20351615556 is an abundant number, since it is smaller than the sum of its proper divisors (27262809148).

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

20351615556 is a wasteful number, since it uses less digits than its factorization.

20351615556 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4547211 (or 4547209 counting only the distinct ones).

The product of its (nonzero) digits is 135000, while the sum is 39.

The spelling of 20351615556 in words is "twenty billion, three hundred fifty-one million, six hundred fifteen thousand, five hundred fifty-six".