21544312460 has 48 divisors (see below), whose sum is σ = 49384732320. Its totient is φ = 7829744640.

The previous prime is 21544312421. The next prime is 21544312481. The reversal of 21544312460 is 6421344512.

It is a super-2 number, since 2×21544312460² (a number of 21 digits) contains 22 as substring.

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, 363386 + ... + 418494.

It is an arithmetic number, because the mean of its divisors is an integer number (1028848590).

Almost surely, 2^21544312460 is an apocalyptic number.

21544312460 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21544312460 is an abundant number, since it is smaller than the sum of its proper divisors (27840419860).

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

21544312460 is a wasteful number, since it uses less digits than its factorization.

21544312460 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 56906 (or 56904 counting only the distinct ones).

The product of its (nonzero) digits is 23040, while the sum is 32.

Adding to 21544312460 its reverse (6421344512), we get a palindrome (27965656972).

The spelling of 21544312460 in words is "twenty-one billion, five hundred forty-four million, three hundred twelve thousand, four hundred sixty".