21696955 has 48 divisors (see below), whose sum is σ = 32832000. Its totient is φ = 13680576.

The previous prime is 21696953. The next prime is 21696967. The reversal of 21696955 is 55969612.

It is not a de Polignac number, because 21696955 - 2¹ = 21696953 is a prime.

It is not an unprimeable number, because it can be changed into a prime (21696953) 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 47 ways as a sum of consecutive naturals, for example, 274606 + ... + 274684.

It is an arithmetic number, because the mean of its divisors is an integer number (684000).

Almost surely, 2^21696955 is an apocalyptic number.

21696955 is a deficient number, since it is larger than the sum of its proper divisors (11135045).

21696955 is a wasteful number, since it uses less digits than its factorization.

21696955 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 176 (or 169 counting only the distinct ones).

The product of its digits is 145800, while the sum is 43.

The square root of 21696955 is about 4657.9990339200. Note that the first 3 decimals coincide. The cubic root of 21696955 is about 278.9113981492.

The spelling of 21696955 in words is "twenty-one million, six hundred ninety-six thousand, nine hundred fifty-five".