21548389464 has 96 divisors (see below), whose sum is σ = 66908293920. Its totient is φ = 6137215488.

The previous prime is 21548389439. The next prime is 21548389481. The reversal of 21548389464 is 46498384512.

21548389464 is a `hidden beast` number, since 2 + 1 + 548 + 3 + 8 + 94 + 6 + 4 = 666.

It is a self number, because there is not a number n which added to its sum of digits gives 21548389464.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 92332 + ... + 227204.

It is an arithmetic number, because the mean of its divisors is an integer number (696961395).

Almost surely, 2^21548389464 is an apocalyptic number.

21548389464 is a gapful number since it is divisible by the number (24) 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 21548389464, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (33454146960).

21548389464 is an abundant number, since it is smaller than the sum of its proper divisors (45359904456).

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

21548389464 is a wasteful number, since it uses less digits than its factorization.

21548389464 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 135209 (or 135202 counting only the distinct ones).

The product of its digits is 6635520, while the sum is 54.

The spelling of 21548389464 in words is "twenty-one billion, five hundred forty-eight million, three hundred eighty-nine thousand, four hundred sixty-four".