21495456 has 60 divisors (see below), whose sum is σ = 63225162. Its totient is φ = 7164288.

The previous prime is 21495451. The next prime is 21495457. The reversal of 21495456 is 65459412.

It can be written as a sum of positive squares in only one way, i.e., 20250000 + 1245456 = 4500^2 + 1116^2 .

It is a super-3 number, since 3×21495456³ (a number of 23 digits) contains 333 as substring.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a self number, because there is not a number n which added to its sum of digits gives 21495456.

It is not an unprimeable number, because it can be changed into a prime (21495451) by changing a digit.

It is a polite number, since it can be written in 9 ways as a sum of consecutive naturals, for example, 1555 + ... + 6738.

Almost surely, 2^21495456 is an apocalyptic number.

It is an amenable number.

21495456 is an abundant number, since it is smaller than the sum of its proper divisors (41729706).

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

21495456 is an equidigital number, since it uses as much as digits as its factorization.

21495456 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8315 (or 8298 counting only the distinct ones).

The product of its digits is 43200, while the sum is 36.

The square root of 21495456 is about 4636.3192297339. The cubic root of 21495456 is about 278.0452973822.

The spelling of 21495456 in words is "twenty-one million, four hundred ninety-five thousand, four hundred fifty-six".