20781292578 has 32 divisors (see below), whose sum is σ = 41995867200. Its totient is φ = 6855204096.

The previous prime is 20781292559. The next prime is 20781292627. The reversal of 20781292578 is 87529218702.

It is a self number, because there is not a number n which added to its sum of digits gives 20781292578.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 221238 + ... + 300846.

It is an arithmetic number, because the mean of its divisors is an integer number (1312370850).

Almost surely, 2^20781292578 is an apocalyptic number.

20781292578 is an abundant number, since it is smaller than the sum of its proper divisors (21214574622).

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

20781292578 is a wasteful number, since it uses less digits than its factorization.

20781292578 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 80066.

The product of its (nonzero) digits is 1128960, while the sum is 51.

The spelling of 20781292578 in words is "twenty billion, seven hundred eighty-one million, two hundred ninety-two thousand, five hundred seventy-eight".