21697862 has 4 divisors (see below), whose sum is σ = 32546796. Its totient is φ = 10848930.

The previous prime is 21697853. The next prime is 21697889. The reversal of 21697862 is 26879612.

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 (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5424464 + ... + 5424467.

It is an arithmetic number, because the mean of its divisors is an integer number (8136699).

Almost surely, 2^21697862 is an apocalyptic number.

21697862 is a deficient number, since it is larger than the sum of its proper divisors (10848934).

21697862 is a wasteful number, since it uses less digits than its factorization.

21697862 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10848933.

The product of its digits is 72576, while the sum is 41.

The square root of 21697862 is about 4658.0963923045. The cubic root of 21697862 is about 278.9152845489.

The spelling of 21697862 in words is "twenty-one million, six hundred ninety-seven thousand, eight hundred sixty-two".