21025452 has 48 divisors (see below), whose sum is σ = 57381632. Its totient is φ = 5866560.

The previous prime is 21025439. The next prime is 21025469. The reversal of 21025452 is 25452012.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (21).

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, 702 + ... + 6522.

Almost surely, 2^21025452 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 21025452, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (28690816).

21025452 is an abundant number, since it is smaller than the sum of its proper divisors (36356180).

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

21025452 is a wasteful number, since it uses less digits than its factorization.

21025452 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5878 (or 5876 counting only the distinct ones).

The product of its (nonzero) digits is 800, while the sum is 21.

The square root of 21025452 is about 4585.3518948931. The cubic root of 21025452 is about 276.0038331751.

Adding to 21025452 its reverse (25452012), we get a palindrome (46477464).

The spelling of 21025452 in words is "twenty-one million, twenty-five thousand, four hundred fifty-two".