20666442 has 8 divisors (see below), whose sum is σ = 41332896. Its totient is φ = 6888812.

The previous prime is 20666413. The next prime is 20666447. The reversal of 20666442 is 24466602.

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

20666442 is an admirable number.

It is not an unprimeable number, because it can be changed into a prime (20666447) 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, 1722198 + ... + 1722209.

It is an arithmetic number, because the mean of its divisors is an integer number (5166612).

Almost surely, 2^20666442 is an apocalyptic number.

20666442 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.

20666442 is a wasteful number, since it uses less digits than its factorization.

20666442 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3444412.

The product of its (nonzero) digits is 13824, while the sum is 30.

The square root of 20666442 is about 4546.0358555559. The cubic root of 20666442 is about 274.4238825980.

The spelling of 20666442 in words is "twenty million, six hundred sixty-six thousand, four hundred forty-two".