21299588 has 6 divisors (see below), whose sum is σ = 37274286. Its totient is φ = 10649792.

The previous prime is 21299561. The next prime is 21299591. The reversal of 21299588 is 88599212.

It can be written as a sum of positive squares in only one way, i.e., 20866624 + 432964 = 4568^2 + 658^2 .

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 2662445 + ... + 2662452.

It is an arithmetic number, because the mean of its divisors is an integer number (6212381).

Almost surely, 2^21299588 is an apocalyptic number.

It is an amenable number.

21299588 is a deficient number, since it is larger than the sum of its proper divisors (15974698).

21299588 is a wasteful number, since it uses less digits than its factorization.

21299588 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5324901 (or 5324899 counting only the distinct ones).

The product of its digits is 103680, while the sum is 44.

The square root of 21299588 is about 4615.1476682767. The cubic root of 21299588 is about 277.1981968958.

The spelling of 21299588 in words is "twenty-one million, two hundred ninety-nine thousand, five hundred eighty-eight".