21002152704 has 144 divisors (see below), whose sum is σ = 60599073024. Its totient is φ = 6418944000.

The previous prime is 21002152681. The next prime is 21002152709. The reversal of 21002152704 is 40725120012.

It is a Harshad number since it is a multiple of its sum of digits (24).

It is not an unprimeable number, because it can be changed into a prime (21002152709) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1500619 + ... + 1514549.

It is an arithmetic number, because the mean of its divisors is an integer number (420826896).

Almost surely, 2^21002152704 is an apocalyptic number.

21002152704 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 21002152704, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (30299536512).

21002152704 is an abundant number, since it is smaller than the sum of its proper divisors (39596920320).

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

21002152704 is a wasteful number, since it uses less digits than its factorization.

21002152704 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 14114 (or 14100 counting only the distinct ones).

The product of its (nonzero) digits is 1120, while the sum is 24.

Adding to 21002152704 its reverse (40725120012), we get a palindrome (61727272716).

The spelling of 21002152704 in words is "twenty-one billion, two million, one hundred fifty-two thousand, seven hundred four".