191507981995 has 12 divisors (see below), whose sum is σ = 252600611760. Its totient is φ = 139278531920.

The previous prime is 191507981983. The next prime is 191507982047. The reversal of 191507981995 is 599189705191.

It is a happy number.

It is not a de Polignac number, because 191507981995 - 2¹³ = 191507973803 is a prime.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 158270455 + ... + 158271664.

It is an arithmetic number, because the mean of its divisors is an integer number (21050050980).

Almost surely, 2^191507981995 is an apocalyptic number.

191507981995 is a deficient number, since it is larger than the sum of its proper divisors (61092629765).

191507981995 is a wasteful number, since it uses less digits than its factorization.

191507981995 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 316542146 (or 316542135 counting only the distinct ones).

The product of its (nonzero) digits is 9185400, while the sum is 64.

The spelling of 191507981995 in words is "one hundred ninety-one billion, five hundred seven million, nine hundred eighty-one thousand, nine hundred ninety-five".