21920580591 has 16 divisors (see below), whose sum is σ = 35972235264. Its totient is φ = 11562503904.

The previous prime is 21920580569. The next prime is 21920580601. The reversal of 21920580591 is 19508502912.

It is not a de Polignac number, because 21920580591 - 2¹⁰ = 21920579567 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21920580091) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 40147311 + ... + 40147856.

It is an arithmetic number, because the mean of its divisors is an integer number (2248264704).

Almost surely, 2^21920580591 is an apocalyptic number.

21920580591 is a gapful number since it is divisible by the number (21) formed by its first and last digit.

21920580591 is a deficient number, since it is larger than the sum of its proper divisors (14051654673).

21920580591 is a wasteful number, since it uses less digits than its factorization.

21920580591 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 80295190.

The product of its (nonzero) digits is 64800, while the sum is 42.

The spelling of 21920580591 in words is "twenty-one billion, nine hundred twenty million, five hundred eighty thousand, five hundred ninety-one".