21879381480 has 128 divisors (see below), whose sum is σ = 75817399680. Its totient is φ = 4992081920.

The previous prime is 21879381479. The next prime is 21879381481. The reversal of 21879381480 is 8418397812.

It is an interprime number because it is at equal distance from previous prime (21879381479) and next prime (21879381481).

It is a Harshad number since it is a multiple of its sum of digits (51).

It is not an unprimeable number, because it can be changed into a prime (21879381481) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 465069 + ... + 509948.

It is an arithmetic number, because the mean of its divisors is an integer number (592323435).

Almost surely, 2^21879381480 is an apocalyptic number.

21879381480 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21879381480 is an abundant number, since it is smaller than the sum of its proper divisors (53938018200).

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

21879381480 is a wasteful number, since it uses less digits than its factorization.

21879381480 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 975059 (or 975055 counting only the distinct ones).

The product of its (nonzero) digits is 774144, while the sum is 51.

The spelling of 21879381480 in words is "twenty-one billion, eight hundred seventy-nine million, three hundred eighty-one thousand, four hundred eighty".