21913736 has 16 divisors (see below), whose sum is σ = 44249100. Its totient is φ = 10113984.

The previous prime is 21913729. The next prime is 21913739. The reversal of 21913736 is 63731912.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 16760836 + 5152900 = 4094^2 + 2270^2 .

It is not an unprimeable number, because it can be changed into a prime (21913739) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 105251 + ... + 105458.

Almost surely, 2^21913736 is an apocalyptic number.

21913736 is a gapful number since it is divisible by the number (26) formed by its first and last digit.

It is an amenable number.

21913736 is an abundant number, since it is smaller than the sum of its proper divisors (22335364).

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

21913736 is a wasteful number, since it uses less digits than its factorization.

21913736 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 210728 (or 210724 counting only the distinct ones).

The product of its digits is 6804, while the sum is 32.

The square root of 21913736 is about 4681.2109544433. The cubic root of 21913736 is about 279.8372183082.

The spelling of 21913736 in words is "twenty-one million, nine hundred thirteen thousand, seven hundred thirty-six".