191591463081 has 16 divisors (see below), whose sum is σ = 259729735680. Its totient is φ = 125599812240.

The previous prime is 191591463067. The next prime is 191591463113. The reversal of 191591463081 is 180364195191.

It is not a de Polignac number, because 191591463081 - 2¹⁰ = 191591462057 is a prime.

It is a super-2 number, since 2×191591463081² (a number of 23 digits) contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 191591463081.

It is not an unprimeable number, because it can be changed into a prime (191591463001) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1092691 + ... + 1255848.

It is an arithmetic number, because the mean of its divisors is an integer number (16233108480).

Almost surely, 2^191591463081 is an apocalyptic number.

It is an amenable number.

191591463081 is a deficient number, since it is larger than the sum of its proper divisors (68138272599).

191591463081 is a wasteful number, since it uses less digits than its factorization.

191591463081 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2348996.

The product of its (nonzero) digits is 233280, while the sum is 48.

The spelling of 191591463081 in words is "one hundred ninety-one billion, five hundred ninety-one million, four hundred sixty-three thousand, eighty-one".