18917451913 has 8 divisors (see below), whose sum is σ = 20031894432. Its totient is φ = 17803192896.

The previous prime is 18917451911. The next prime is 18917451923. The reversal of 18917451913 is 31915471981.

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 18917451913 - 2¹ = 18917451911 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (18917451911) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 205906 + ... + 283252.

It is an arithmetic number, because the mean of its divisors is an integer number (2503986804).

Almost surely, 2^18917451913 is an apocalyptic number.

It is an amenable number.

18917451913 is a deficient number, since it is larger than the sum of its proper divisors (1114442519).

18917451913 is a wasteful number, since it uses less digits than its factorization.

18917451913 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 91751.

The product of its digits is 272160, while the sum is 49.

The spelling of 18917451913 in words is "eighteen billion, nine hundred seventeen million, four hundred fifty-one thousand, nine hundred thirteen".