21134400320 has 112 divisors (see below), whose sum is σ = 55415492928. Its totient is φ = 7613276160.

The previous prime is 21134400317. The next prime is 21134400341. The reversal of 21134400320 is 2300443112.

It is a super-2 number, since 2×21134400320² (a number of 21 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (20).

It is a junction number, because it is equal to n+sod(n) for n = 21134400292 and 21134400301.

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, 348584 + ... + 404696.

Almost surely, 2^21134400320 is an apocalyptic number.

21134400320 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 21134400320, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (27707746464).

21134400320 is an abundant number, since it is smaller than the sum of its proper divisors (34281092608).

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

21134400320 is a wasteful number, since it uses less digits than its factorization.

21134400320 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 56248 (or 56238 counting only the distinct ones).

The product of its (nonzero) digits is 576, while the sum is 20.

Adding to 21134400320 its reverse (2300443112), we get a palindrome (23434843432).

The spelling of 21134400320 in words is "twenty-one billion, one hundred thirty-four million, four hundred thousand, three hundred twenty".