20664442 has 8 divisors (see below), whose sum is σ = 32344416. Its totient is φ = 9882972.

The previous prime is 20664437. The next prime is 20664461. The reversal of 20664442 is 24446602.

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

It is a self number, because there is not a number n which added to its sum of digits gives 20664442.

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, 224568 + ... + 224659.

It is an arithmetic number, because the mean of its divisors is an integer number (4043052).

Almost surely, 2^20664442 is an apocalyptic number.

20664442 is a deficient number, since it is larger than the sum of its proper divisors (11679974).

20664442 is a wasteful number, since it uses less digits than its factorization.

20664442 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 449252.

The product of its (nonzero) digits is 9216, while the sum is 28.

The square root of 20664442 is about 4545.8158783655. The cubic root of 20664442 is about 274.4150298329.

The spelling of 20664442 in words is "twenty million, six hundred sixty-four thousand, four hundred forty-two".