21203396 has 12 divisors (see below), whose sum is σ = 38011260. Its totient is φ = 10343040.

The previous prime is 21203383. The next prime is 21203407. The reversal of 21203396 is 69330212.

It can be written as a sum of positive squares in 2 ways, for example, as 6071296 + 15132100 = 2464^2 + 3890^2 .

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, 64481 + ... + 64808.

It is an arithmetic number, because the mean of its divisors is an integer number (3167605).

Almost surely, 2^21203396 is an apocalyptic number.

It is an amenable number.

21203396 is a deficient number, since it is larger than the sum of its proper divisors (16807864).

21203396 is a wasteful number, since it uses less digits than its factorization.

21203396 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 129334 (or 129332 counting only the distinct ones).

The product of its (nonzero) digits is 1944, while the sum is 26.

The square root of 21203396 is about 4604.7145405551. The cubic root of 21203396 is about 276.7802781732.

The spelling of 21203396 in words is "twenty-one million, two hundred three thousand, three hundred ninety-six".