21487258456 has 32 divisors (see below), whose sum is σ = 40795473600. Its totient is φ = 10608602400.

The previous prime is 21487258451. The next prime is 21487258459. The reversal of 21487258456 is 65485278412.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21487258451) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1439431 + ... + 1454281.

It is an arithmetic number, because the mean of its divisors is an integer number (1274858550).

Almost surely, 2^21487258456 is an apocalyptic number.

It is an amenable number.

21487258456 is a deficient number, since it is larger than the sum of its proper divisors (19308215144).

21487258456 is a wasteful number, since it uses less digits than its factorization.

21487258456 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 17119 (or 17115 counting only the distinct ones).

The product of its digits is 4300800, while the sum is 52.

The spelling of 21487258456 in words is "twenty-one billion, four hundred eighty-seven million, two hundred fifty-eight thousand, four hundred fifty-six".