21099268 has 6 divisors (see below), whose sum is σ = 36923726. Its totient is φ = 10549632.

The previous prime is 21099187. The next prime is 21099277. The reversal of 21099268 is 86299012.

It can be written as a sum of positive squares in only one way, i.e., 17288964 + 3810304 = 4158^2 + 1952^2 .

It is a super-2 number, since 2×21099268² = 890358220271648, which contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 2637405 + ... + 2637412.

Almost surely, 2^21099268 is an apocalyptic number.

It is an amenable number.

21099268 is a deficient number, since it is larger than the sum of its proper divisors (15824458).

21099268 is a wasteful number, since it uses less digits than its factorization.

21099268 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5274821 (or 5274819 counting only the distinct ones).

The product of its (nonzero) digits is 15552, while the sum is 37.

The square root of 21099268 is about 4593.3939521883. The cubic root of 21099268 is about 276.3264533177.

The spelling of 21099268 in words is "twenty-one million, ninety-nine thousand, two hundred sixty-eight".