20858731881 has 24 divisors (see below), whose sum is σ = 30426107040. Its totient is φ = 12703781376.

The previous prime is 20858731871. The next prime is 20858731913. The reversal of 20858731881 is 18813785802.

It is not a de Polignac number, because 20858731881 - 2⁵ = 20858731849 is a prime.

It is a super-2 number, since 2×20858731881² (a number of 21 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (20858731801) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 162891 + ... + 261248.

It is an arithmetic number, because the mean of its divisors is an integer number (1267754460).

Almost surely, 2^20858731881 is an apocalyptic number.

It is an amenable number.

20858731881 is a deficient number, since it is larger than the sum of its proper divisors (9567375159).

20858731881 is a wasteful number, since it uses less digits than its factorization.

20858731881 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 424265 (or 424252 counting only the distinct ones).

The product of its (nonzero) digits is 860160, while the sum is 51.

The spelling of 20858731881 in words is "twenty billion, eight hundred fifty-eight million, seven hundred thirty-one thousand, eight hundred eighty-one".