18951916205 has 8 divisors (see below), whose sum is σ = 22771201632. Its totient is φ = 15142264848.

The previous prime is 18951916199. The next prime is 18951916213. The reversal of 18951916205 is 50261915981.

It is a happy number.

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

It is a cyclic number.

It is not a de Polignac number, because 18951916205 - 2¹⁶ = 18951850669 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 18951916205.

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 7 ways as a sum of consecutive naturals, for example, 2404187 + ... + 2412056.

It is an arithmetic number, because the mean of its divisors is an integer number (2846400204).

Almost surely, 2^18951916205 is an apocalyptic number.

It is an amenable number.

18951916205 is a deficient number, since it is larger than the sum of its proper divisors (3819285427).

18951916205 is an equidigital number, since it uses as much as digits as its factorization.

18951916205 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4817035.

The product of its (nonzero) digits is 194400, while the sum is 47.

The spelling of 18951916205 in words is "eighteen billion, nine hundred fifty-one million, nine hundred sixteen thousand, two hundred five".