20159918 has 4 divisors (see below), whose sum is σ = 30239880. Its totient is φ = 10079958.

The previous prime is 20159917. The next prime is 20159929. The reversal of 20159918 is 81995102.

It is a semiprime because it is the product of two primes.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20159911) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5039978 + ... + 5039981.

It is an arithmetic number, because the mean of its divisors is an integer number (7559970).

Almost surely, 2^20159918 is an apocalyptic number.

20159918 is a deficient number, since it is larger than the sum of its proper divisors (10079962).

20159918 is a wasteful number, since it uses less digits than its factorization.

20159918 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10079961.

The product of its (nonzero) digits is 6480, while the sum is 35.

The square root of 20159918 is about 4489.9797326937. The cubic root of 20159918 is about 272.1633156326.

The spelling of 20159918 in words is "twenty million, one hundred fifty-nine thousand, nine hundred eighteen".