18749950121 has 4 divisors (see below), whose sum is σ = 21428514432. Its totient is φ = 16071385812.

The previous prime is 18749950111. The next prime is 18749950151. The reversal of 18749950121 is 12105994781.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 18749950121 - 2⁶ = 18749950057 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (18749950111) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1339282145 + ... + 1339282158.

It is an arithmetic number, because the mean of its divisors is an integer number (5357128608).

Almost surely, 2^18749950121 is an apocalyptic number.

It is an amenable number.

18749950121 is a deficient number, since it is larger than the sum of its proper divisors (2678564311).

18749950121 is an equidigital number, since it uses as much as digits as its factorization.

18749950121 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2678564310.

The product of its (nonzero) digits is 181440, while the sum is 47.

The spelling of 18749950121 in words is "eighteen billion, seven hundred forty-nine million, nine hundred fifty thousand, one hundred twenty-one".