21795899580 has 864 divisors, whose sum is σ = 90242740224. Its totient is φ = 4308774912.

The previous prime is 21795899557. The next prime is 21795899621. The reversal of 21795899580 is 8599859712.

It is a super-2 number, since 2×21795899580² (a number of 21 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (63).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 287 ways as a sum of consecutive naturals, for example, 97739349 + ... + 97739571.

It is an arithmetic number, because the mean of its divisors is an integer number (104447616).

Almost surely, 2^21795899580 is an apocalyptic number.

21795899580 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 21795899580, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (45121370112).

21795899580 is an abundant number, since it is smaller than the sum of its proper divisors (68446840644).

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

21795899580 is a wasteful number, since it uses less digits than its factorization.

21795899580 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 297 (or 270 counting only the distinct ones).

The product of its (nonzero) digits is 16329600, while the sum is 63.

The spelling of 21795899580 in words is "twenty-one billion, seven hundred ninety-five million, eight hundred ninety-nine thousand, five hundred eighty".