21477079608 has 128 divisors (see below), whose sum is σ = 59385830400. Its totient is φ = 6442039296.

The previous prime is 21477079597. The next prime is 21477079619. The reversal of 21477079608 is 80697077412.

It is an interprime number because it is at equal distance from previous prime (21477079597) and next prime (21477079619).

It is a super-2 number, since 2×21477079608² (a number of 21 digits) contains 22 as substring.

It is a Smith number, since the sum of its digits (51) coincides with the sum of the digits of its prime factors.

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

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 1209885 + ... + 1227507.

It is an arithmetic number, because the mean of its divisors is an integer number (463951800).

Almost surely, 2^21477079608 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21477079608, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (29692915200).

21477079608 is an abundant number, since it is smaller than the sum of its proper divisors (37908750792).

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

21477079608 is a wasteful number, since it uses less digits than its factorization.

21477079608 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 17781 (or 17777 counting only the distinct ones).

The product of its (nonzero) digits is 1185408, while the sum is 51.

The spelling of 21477079608 in words is "twenty-one billion, four hundred seventy-seven million, seventy-nine thousand, six hundred eight".