21761406220 has 24 divisors (see below), whose sum is σ = 45724097664. Its totient is φ = 8699773056.

The previous prime is 21761406217. The next prime is 21761406241. The reversal of 21761406220 is 2260416712.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 261969 + ... + 334888.

It is an arithmetic number, because the mean of its divisors is an integer number (1905170736).

Almost surely, 2^21761406220 is an apocalyptic number.

21761406220 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21761406220 is an abundant number, since it is smaller than the sum of its proper divisors (23962691444).

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

21761406220 is a wasteful number, since it uses less digits than its factorization.

21761406220 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 598689 (or 598687 counting only the distinct ones).

The product of its (nonzero) digits is 8064, while the sum is 31.

The spelling of 21761406220 in words is "twenty-one billion, seven hundred sixty-one million, four hundred six thousand, two hundred twenty".