18720642 has 8 divisors (see below), whose sum is σ = 37441296. Its totient is φ = 6240212.

The previous prime is 18720619. The next prime is 18720661. The reversal of 18720642 is 24602781.

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

18720642 is an admirable number.

It is a plaindrome in base 15.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1560048 + ... + 1560059.

It is an arithmetic number, because the mean of its divisors is an integer number (4680162).

Almost surely, 2^18720642 is an apocalyptic number.

18720642 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.

18720642 is a wasteful number, since it uses less digits than its factorization.

18720642 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3120112.

The product of its (nonzero) digits is 5376, while the sum is 30.

The square root of 18720642 is about 4326.7357210719. The cubic root of 18720642 is about 265.5259141754.

The spelling of 18720642 in words is "eighteen million, seven hundred twenty thousand, six hundred forty-two".