21130051440 has 160 divisors (see below), whose sum is σ = 65970777600. Its totient is φ = 5594637312.

The previous prime is 21130051421. The next prime is 21130051471. The reversal of 21130051440 is 4415003112.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 29064357 + ... + 29065083.

It is an arithmetic number, because the mean of its divisors is an integer number (412317360).

Almost surely, 2^21130051440 is an apocalyptic number.

21130051440 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 21130051440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (32985388800).

21130051440 is an abundant number, since it is smaller than the sum of its proper divisors (44840726160).

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

21130051440 is a wasteful number, since it uses less digits than its factorization.

21130051440 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1439 (or 1433 counting only the distinct ones).

The product of its (nonzero) digits is 480, while the sum is 21.

Adding to 21130051440 its reverse (4415003112), we get a palindrome (25545054552).

The spelling of 21130051440 in words is "twenty-one billion, one hundred thirty million, fifty-one thousand, four hundred forty".