21942574 has 8 divisors (see below), whose sum is σ = 32933880. Its totient is φ = 10964616.

The previous prime is 21942539. The next prime is 21942577. The reversal of 21942574 is 47524912.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21942577) 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 3 ways as a sum of consecutive naturals, for example, 4012 + ... + 7744.

It is an arithmetic number, because the mean of its divisors is an integer number (4116735).

Almost surely, 2^21942574 is an apocalyptic number.

21942574 is a deficient number, since it is larger than the sum of its proper divisors (10991306).

21942574 is a wasteful number, since it uses less digits than its factorization.

21942574 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6674.

The product of its digits is 20160, while the sum is 34.

The square root of 21942574 is about 4684.2901276501. The cubic root of 21942574 is about 279.9599177318.

The spelling of 21942574 in words is "twenty-one million, nine hundred forty-two thousand, five hundred seventy-four".