191399945 has 8 divisors (see below), whose sum is σ = 250560000. Its totient is φ = 139199920.

The previous prime is 191399917. The next prime is 191399981. The reversal of 191399945 is 549993191.

It is a happy number.

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

It is not a de Polignac number, because 191399945 - 2²⁴ = 174622729 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 191399893 and 191399902.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1739945 + ... + 1740054.

It is an arithmetic number, because the mean of its divisors is an integer number (31320000).

Almost surely, 2^191399945 is an apocalyptic number.

It is an amenable number.

191399945 is a deficient number, since it is larger than the sum of its proper divisors (59160055).

191399945 is a wasteful number, since it uses less digits than its factorization.

191399945 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3480015.

The product of its digits is 393660, while the sum is 50.

The square root of 191399945 is about 13834.7368966670. The cubic root of 191399945 is about 576.2982085356.

The spelling of 191399945 in words is "one hundred ninety-one million, three hundred ninety-nine thousand, nine hundred forty-five".