21085452 has 36 divisors (see below), whose sum is σ = 53508000. Its totient is φ = 7000992.

The previous prime is 21085409. The next prime is 21085453. The reversal of 21085452 is 25458012.

It is a happy number.

It is a tau number, because it is divible by the number of its divisors (36).

It is not an unprimeable number, because it can be changed into a prime (21085453) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 9549 + ... + 11547.

Almost surely, 2^21085452 is an apocalyptic number.

It is an amenable number.

21085452 is an abundant number, since it is smaller than the sum of its proper divisors (32422548).

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

21085452 is a wasteful number, since it uses less digits than its factorization.

21085452 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2302 (or 2297 counting only the distinct ones).

The product of its (nonzero) digits is 3200, while the sum is 27.

The square root of 21085452 is about 4591.8898070402. The cubic root of 21085452 is about 276.2661264243.

The spelling of 21085452 in words is "twenty-one million, eighty-five thousand, four hundred fifty-two".