21304396 has 12 divisors (see below), whose sum is σ = 39245080. Its totient is φ = 10091520.

The previous prime is 21304373. The next prime is 21304397. The reversal of 21304396 is 69340312.

It is a hoax number, since the sum of its digits (28) coincides with the sum of the digits of its distinct prime factors.

It is not an unprimeable number, because it can be changed into a prime (21304397) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 140085 + ... + 140236.

Almost surely, 2^21304396 is an apocalyptic number.

It is an amenable number.

21304396 is a deficient number, since it is larger than the sum of its proper divisors (17940684).

21304396 is a wasteful number, since it uses less digits than its factorization.

21304396 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 280344 (or 280342 counting only the distinct ones).

The product of its (nonzero) digits is 3888, while the sum is 28.

The square root of 21304396 is about 4615.6685322930. The cubic root of 21304396 is about 277.2190528338.

The spelling of 21304396 in words is "twenty-one million, three hundred four thousand, three hundred ninety-six".