18951916238 has 8 divisors (see below), whose sum is σ = 28428536280. Its totient is φ = 9475737480.

The previous prime is 18951916213. The next prime is 18951916241. The reversal of 18951916238 is 83261915981.

It is a happy number.

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 18951916238.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 35708 + ... + 197936.

It is an arithmetic number, because the mean of its divisors is an integer number (3553567035).

Almost surely, 2^18951916238 is an apocalyptic number.

18951916238 is a deficient number, since it is larger than the sum of its proper divisors (9476620042).

18951916238 is a wasteful number, since it uses less digits than its factorization.

18951916238 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 220642.

The product of its digits is 933120, while the sum is 53.

The spelling of 18951916238 in words is "eighteen billion, nine hundred fifty-one million, nine hundred sixteen thousand, two hundred thirty-eight".