20856505376 has 48 divisors (see below), whose sum is σ = 48440931840. Its totient is φ = 8650160640.

The previous prime is 20856505279. The next prime is 20856505381. The reversal of 20856505376 is 67350565802.

It is a self number, because there is not a number n which added to its sum of digits gives 20856505376.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1494821 + ... + 1508708.

It is an arithmetic number, because the mean of its divisors is an integer number (1009186080).

Almost surely, 2^20856505376 is an apocalyptic number.

It is an amenable number.

20856505376 is an abundant number, since it is smaller than the sum of its proper divisors (27584426464).

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

20856505376 is a wasteful number, since it uses less digits than its factorization.

20856505376 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3003577 (or 3003569 counting only the distinct ones).

The product of its (nonzero) digits is 1512000, while the sum is 47.

The spelling of 20856505376 in words is "twenty billion, eight hundred fifty-six million, five hundred five thousand, three hundred seventy-six".