21971374 has 8 divisors (see below), whose sum is σ = 34020288. Its totient is φ = 10631280.

The previous prime is 21971359. The next prime is 21971387. The reversal of 21971374 is 47317912.

It is a sphenic number, since it is the product of 3 distinct 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 in 3 ways as a sum of consecutive naturals, for example, 177127 + ... + 177250.

It is an arithmetic number, because the mean of its divisors is an integer number (4252536).

Almost surely, 2^21971374 is an apocalyptic number.

21971374 is a deficient number, since it is larger than the sum of its proper divisors (12048914).

21971374 is a wasteful number, since it uses less digits than its factorization.

21971374 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 354410.

The product of its digits is 10584, while the sum is 34.

The square root of 21971374 is about 4687.3632246712. The cubic root of 21971374 is about 280.0823482279.

The spelling of 21971374 in words is "twenty-one million, nine hundred seventy-one thousand, three hundred seventy-four".