21974718 has 8 divisors (see below), whose sum is σ = 43949448. Its totient is φ = 7324904.

The previous prime is 21974717. The next prime is 21974731. The reversal of 21974718 is 81747912.

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

21974718 is an admirable number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21974717) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1831221 + ... + 1831232.

It is an arithmetic number, because the mean of its divisors is an integer number (5493681).

Almost surely, 2^21974718 is an apocalyptic number.

21974718 is a primitive abundant number, since it is smaller than the sum of its proper divisors, none of which is abundant.

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21974718 is a wasteful number, since it uses less digits than its factorization.

21974718 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3662458.

The product of its digits is 28224, while the sum is 39.

The square root of 21974718 is about 4687.7199148413. The cubic root of 21974718 is about 280.0965568350.

The spelling of 21974718 in words is "twenty-one million, nine hundred seventy-four thousand, seven hundred eighteen".