21917386484 has 48 divisors (see below), whose sum is σ = 44999904768. Its totient is φ = 9145571328.

The previous prime is 21917386453. The next prime is 21917386501. The reversal of 21917386484 is 48468371912.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 210842 + ... + 297134.

It is an arithmetic number, because the mean of its divisors is an integer number (937498016).

Almost surely, 2^21917386484 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 21917386484, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (22499952384).

21917386484 is an abundant number, since it is smaller than the sum of its proper divisors (23082518284).

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

21917386484 is a wasteful number, since it uses less digits than its factorization.

21917386484 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 86544 (or 86542 counting only the distinct ones).

The product of its digits is 2322432, while the sum is 53.

The spelling of 21917386484 in words is "twenty-one billion, nine hundred seventeen million, three hundred eighty-six thousand, four hundred eighty-four".