21256452 has 96 divisors (see below), whose sum is σ = 65085440. Its totient is φ = 5870880.

The previous prime is 21256447. The next prime is 21256457. The reversal of 21256452 is 25465212.

21256452 is a `hidden beast` number, since 2 + 12 + 5 + 645 + 2 = 666.

It is an interprime number because it is at equal distance from previous prime (21256447) and next prime (21256457).

It is a super-3 number, since 3×21256452³ (a number of 23 digits) contains 333 as substring.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is not an unprimeable number, because it can be changed into a prime (21256457) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 22983 + ... + 23889.

Almost surely, 2^21256452 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21256452, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (32542720).

21256452 is an abundant number, since it is smaller than the sum of its proper divisors (43828988).

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

21256452 is a wasteful number, since it uses less digits than its factorization.

21256452 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 958 (or 950 counting only the distinct ones).

The product of its digits is 4800, while the sum is 27.

The square root of 21256452 is about 4610.4719931912. The cubic root of 21256452 is about 277.0109428443.

The spelling of 21256452 in words is "twenty-one million, two hundred fifty-six thousand, four hundred fifty-two".