21299736 has 32 divisors (see below), whose sum is σ = 54126000. Its totient is φ = 6983040.

The previous prime is 21299713. The next prime is 21299737. The reversal of 21299736 is 63799212.

It is a Smith number, since the sum of its digits (39) coincides with the sum of the digits of its prime factors.

It is a junction number, because it is equal to n+sod(n) for n = 21299694 and 21299703.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21299737) by changing a digit.

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 in 7 ways as a sum of consecutive naturals, for example, 5811 + ... + 8738.

Almost surely, 2^21299736 is an apocalyptic number.

It is an amenable number.

21299736 is an abundant number, since it is smaller than the sum of its proper divisors (32826264).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21299736 is a wasteful number, since it uses less digits than its factorization.

21299736 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 14619 (or 14615 counting only the distinct ones).

The product of its digits is 40824, while the sum is 39.

The square root of 21299736 is about 4615.1637024054. The cubic root of 21299736 is about 277.1988389308.

The spelling of 21299736 in words is "twenty-one million, two hundred ninety-nine thousand, seven hundred thirty-six".