21023251360 has 96 divisors (see below), whose sum is σ = 50887850832. Its totient is φ = 8204451840.

The previous prime is 21023251313. The next prime is 21023251363. The reversal of 21023251360 is 6315232012.

It can be written as a sum of positive squares in 8 ways, for example, as 634838416 + 20388412944 = 25196^2 + 142788^2 .

It is not an unprimeable number, because it can be changed into a prime (21023251363) 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, 1528032 + ... + 1541728.

Almost surely, 2^21023251360 is an apocalyptic number.

21023251360 is a gapful number since it is divisible by the number (20) 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 21023251360, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (25443925416).

21023251360 is an abundant number, since it is smaller than the sum of its proper divisors (29864599472).

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

21023251360 is a wasteful number, since it uses less digits than its factorization.

21023251360 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 13946 (or 13938 counting only the distinct ones).

The product of its (nonzero) digits is 2160, while the sum is 25.

Adding to 21023251360 its reverse (6315232012), we get a palindrome (27338483372).

The spelling of 21023251360 in words is "twenty-one billion, twenty-three million, two hundred fifty-one thousand, three hundred sixty".