21243802 has 8 divisors (see below), whose sum is σ = 31936212. Its totient is φ = 10598400.

The previous prime is 21243793. The next prime is 21243821. The reversal of 21243802 is 20834212.

It can be written as a sum of positive squares in 2 ways, for example, as 19900521 + 1343281 = 4461^2 + 1159^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is an unprimeable number.

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 3 ways as a sum of consecutive naturals, for example, 10599 + ... + 12442.

Almost surely, 2^21243802 is an apocalyptic number.

21243802 is a deficient number, since it is larger than the sum of its proper divisors (10692410).

21243802 is a wasteful number, since it uses less digits than its factorization.

21243802 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 23504.

The product of its (nonzero) digits is 768, while the sum is 22.

The square root of 21243802 is about 4609.0999121303. The cubic root of 21243802 is about 276.9559809628.

The spelling of 21243802 in words is "twenty-one million, two hundred forty-three thousand, eight hundred two".