18979958 has 4 divisors (see below), whose sum is σ = 28469940. Its totient is φ = 9489978.

The previous prime is 18979957. The next prime is 18979999. The reversal of 18979958 is 85997981.

It is a happy number.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 85997981 = 2837 ⋅30313.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18979951) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 4744988 + ... + 4744991.

It is an arithmetic number, because the mean of its divisors is an integer number (7117485).

Almost surely, 2^18979958 is an apocalyptic number.

18979958 is a deficient number, since it is larger than the sum of its proper divisors (9489982).

18979958 is an equidigital number, since it uses as much as digits as its factorization.

18979958 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9489981.

The product of its digits is 1632960, while the sum is 56.

The square root of 18979958 is about 4356.5993618877. The cubic root of 18979958 is about 266.7463071157.

The spelling of 18979958 in words is "eighteen million, nine hundred seventy-nine thousand, nine hundred fifty-eight".