21997336 has 8 divisors (see below), whose sum is σ = 41245020. Its totient is φ = 10998664.

The previous prime is 21997333. The next prime is 21997357. The reversal of 21997336 is 63379912.

It is a tau number, because it is divible by the number of its divisors (8).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21997331) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1374826 + ... + 1374841.

Almost surely, 2^21997336 is an apocalyptic number.

It is an amenable number.

21997336 is a deficient number, since it is larger than the sum of its proper divisors (19247684).

21997336 is a wasteful number, since it uses less digits than its factorization.

21997336 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2749673 (or 2749669 counting only the distinct ones).

The product of its digits is 61236, while the sum is 40.

The square root of 21997336 is about 4690.1317678718. The cubic root of 21997336 is about 280.1926225593.

The spelling of 21997336 in words is "twenty-one million, nine hundred ninety-seven thousand, three hundred thirty-six".