21963497 has 8 divisors (see below), whose sum is σ = 22544544. Its totient is φ = 21385728.

The previous prime is 21963481. The next prime is 21963499. The reversal of 21963497 is 79436912.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 21963497 - 2⁴ = 21963481 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21963499) 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 in 7 ways as a sum of consecutive naturals, for example, 18473 + ... + 19625.

It is an arithmetic number, because the mean of its divisors is an integer number (2818068).

Almost surely, 2^21963497 is an apocalyptic number.

It is an amenable number.

21963497 is a deficient number, since it is larger than the sum of its proper divisors (581047).

21963497 is a wasteful number, since it uses less digits than its factorization.

21963497 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1639.

The product of its digits is 81648, while the sum is 41.

The square root of 21963497 is about 4686.5229114985. The cubic root of 21963497 is about 280.0488732715.

The spelling of 21963497 in words is "twenty-one million, nine hundred sixty-three thousand, four hundred ninety-seven".