20858778578 has 32 divisors (see below), whose sum is σ = 34296514560. Its totient is φ = 9435834000.

The previous prime is 20858778559. The next prime is 20858778587. The reversal of 20858778578 is 87587785802.

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, 4160093 + ... + 4165103.

It is an arithmetic number, because the mean of its divisors is an integer number (1071766080).

Almost surely, 2^20858778578 is an apocalyptic number.

20858778578 is a deficient number, since it is larger than the sum of its proper divisors (13437735982).

20858778578 is a wasteful number, since it uses less digits than its factorization.

20858778578 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5894.

The product of its (nonzero) digits is 70246400, while the sum is 65.

The spelling of 20858778578 in words is "twenty billion, eight hundred fifty-eight million, seven hundred seventy-eight thousand, five hundred seventy-eight".