21683497 has 8 divisors (see below), whose sum is σ = 24158592. Its totient is φ = 19292400.

The previous prime is 21683491. The next prime is 21683507. The reversal of 21683497 is 79438612.

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 21683497 - 2¹¹ = 21681449 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21683491) 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, 20454 + ... + 21487.

It is an arithmetic number, because the mean of its divisors is an integer number (3019824).

Almost surely, 2^21683497 is an apocalyptic number.

It is an amenable number.

21683497 is a deficient number, since it is larger than the sum of its proper divisors (2475095).

21683497 is a wasteful number, since it uses less digits than its factorization.

21683497 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 41999.

The product of its digits is 72576, while the sum is 40.

The square root of 21683497 is about 4656.5541981169. The cubic root of 21683497 is about 278.8537193037.

It can be divided in two parts, 2168 and 3497, that added together give a palindrome (5665).

The spelling of 21683497 in words is "twenty-one million, six hundred eighty-three thousand, four hundred ninety-seven".