21523676580 has 144 divisors (see below), whose sum is σ = 74789629824. Its totient is φ = 4908211200.

The previous prime is 21523676569. The next prime is 21523676677. The reversal of 21523676580 is 8567632512.

21523676580 is a `hidden beast` number, since 2 + 1 + 5 + 2 + 3 + 67 + 6 + 580 = 666.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 525855 + ... + 565305.

Almost surely, 2^21523676580 is an apocalyptic number.

21523676580 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21523676580, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (37394814912).

21523676580 is an abundant number, since it is smaller than the sum of its proper divisors (53265953244).

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

21523676580 is a wasteful number, since it uses less digits than its factorization.

21523676580 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 39906 (or 39901 counting only the distinct ones).

The product of its (nonzero) digits is 604800, while the sum is 45.

The spelling of 21523676580 in words is "twenty-one billion, five hundred twenty-three million, six hundred seventy-six thousand, five hundred eighty".