21570052 has 12 divisors (see below), whose sum is σ = 43140160. Its totient is φ = 9244296.

The previous prime is 21570049. The next prime is 21570053. The reversal of 21570052 is 25007512.

21570052 is an admirable number.

It is not an unprimeable number, because it can be changed into a prime (21570053) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 385152 + ... + 385207.

Almost surely, 2^21570052 is an apocalyptic number.

It is an amenable number.

21570052 is a primitive abundant number, since it is smaller than the sum of its proper divisors, none of which is abundant.

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

21570052 is a wasteful number, since it uses less digits than its factorization.

21570052 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 770370 (or 770368 counting only the distinct ones).

The product of its (nonzero) digits is 700, while the sum is 22.

The square root of 21570052 is about 4644.3570060881. The cubic root of 21570052 is about 278.3665609472.

Adding to 21570052 its reverse (25007512), we get a palindrome (46577564).

The spelling of 21570052 in words is "twenty-one million, five hundred seventy thousand, fifty-two".