21997174 has 12 divisors (see below), whose sum is σ = 34824924. Its totient is φ = 10419372.

The previous prime is 21997159. The next prime is 21997187. The reversal of 21997174 is 47179912.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 14512 + ... + 15955.

It is an arithmetic number, because the mean of its divisors is an integer number (2902077).

Almost surely, 2^21997174 is an apocalyptic number.

21997174 is a deficient number, since it is larger than the sum of its proper divisors (12827750).

21997174 is a wasteful number, since it uses less digits than its factorization.

21997174 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 30507 (or 30488 counting only the distinct ones).

The product of its digits is 31752, while the sum is 40.

The square root of 21997174 is about 4690.1144975363. The cubic root of 21997174 is about 280.1919347288.

The spelling of 21997174 in words is "twenty-one million, nine hundred ninety-seven thousand, one hundred seventy-four".