21245704 has 16 divisors (see below), whose sum is σ = 40013100. Its totient is φ = 10575552.

The previous prime is 21245683. The next prime is 21245713. The reversal of 21245704 is 40754212.

It can be written as a sum of positive squares in 2 ways, for example, as 16793604 + 4452100 = 4098^2 + 2110^2 .

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3967 + ... + 7630.

Almost surely, 2^21245704 is an apocalyptic number.

It is an amenable number.

21245704 is a deficient number, since it is larger than the sum of its proper divisors (18767396).

21245704 is a wasteful number, since it uses less digits than its factorization.

21245704 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11832 (or 11828 counting only the distinct ones).

The product of its (nonzero) digits is 2240, while the sum is 25.

The square root of 21245704 is about 4609.3062384702. The cubic root of 21245704 is about 276.9642461901.

Adding to 21245704 its reverse (40754212), we get a palindrome (61999916).

The spelling of 21245704 in words is "twenty-one million, two hundred forty-five thousand, seven hundred four".