21665702 has 4 divisors (see below), whose sum is σ = 32498556. Its totient is φ = 10832850.

The previous prime is 21665689. The next prime is 21665713. The reversal of 21665702 is 20756612.

It is a semiprime because it is the product of two primes.

It is a congruent number.

It is an unprimeable number.

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, 5416424 + ... + 5416427.

It is an arithmetic number, because the mean of its divisors is an integer number (8124639).

Almost surely, 2^21665702 is an apocalyptic number.

21665702 is a deficient number, since it is larger than the sum of its proper divisors (10832854).

21665702 is a wasteful number, since it uses less digits than its factorization.

21665702 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10832853.

The product of its (nonzero) digits is 5040, while the sum is 29.

The square root of 21665702 is about 4654.6430582806. The cubic root of 21665702 is about 278.7774161134. Note that the first 3 decimals are identical.

The spelling of 21665702 in words is "twenty-one million, six hundred sixty-five thousand, seven hundred two".