21299332 has 6 divisors (see below), whose sum is σ = 37273838. Its totient is φ = 10649664.

The previous prime is 21299329. The next prime is 21299371. The reversal of 21299332 is 23399212.

It is a happy number.

It can be written as a sum of positive squares in only one way, i.e., 16128256 + 5171076 = 4016^2 + 2274^2 .

It is a junction number, because it is equal to n+sod(n) for n = 21299294 and 21299303.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 2662413 + ... + 2662420.

Almost surely, 2^21299332 is an apocalyptic number.

It is an amenable number.

21299332 is a deficient number, since it is larger than the sum of its proper divisors (15974506).

21299332 is a wasteful number, since it uses less digits than its factorization.

21299332 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5324837 (or 5324835 counting only the distinct ones).

The product of its digits is 5832, while the sum is 31.

The square root of 21299332 is about 4615.1199334362. The cubic root of 21299332 is about 277.1970863419.

The spelling of 21299332 in words is "twenty-one million, two hundred ninety-nine thousand, three hundred thirty-two".