18953918 has 4 divisors (see below), whose sum is σ = 28430880. Its totient is φ = 9476958.

The previous prime is 18953911. The next prime is 18953923. The reversal of 18953918 is 81935981.

It is a happy number.

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 (18953911) by changing a digit.

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 as a sum of consecutive naturals, namely, 4738478 + ... + 4738481.

It is an arithmetic number, because the mean of its divisors is an integer number (7107720).

Almost surely, 2^18953918 is an apocalyptic number.

18953918 is a deficient number, since it is larger than the sum of its proper divisors (9476962).

18953918 is an equidigital number, since it uses as much as digits as its factorization.

18953918 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9476961.

The product of its digits is 77760, while the sum is 44.

The square root of 18953918 is about 4353.6097666190. The cubic root of 18953918 is about 266.6242616599.

The spelling of 18953918 in words is "eighteen million, nine hundred fifty-three thousand, nine hundred eighteen".