191257055 has 32 divisors (see below), whose sum is σ = 269671680. Its totient is φ = 128657920.

The previous prime is 191257049. The next prime is 191257057. The reversal of 191257055 is 550752191.

It is not a de Polignac number, because 191257055 - 2¹⁴ = 191240671 is a prime.

It is a super-2 number, since 2×191257055² = 73158522174546050, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (191257057) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 53432 + ... + 56898.

It is an arithmetic number, because the mean of its divisors is an integer number (8427240).

Almost surely, 2^191257055 is an apocalyptic number.

191257055 is a deficient number, since it is larger than the sum of its proper divisors (78414625).

191257055 is a wasteful number, since it uses less digits than its factorization.

191257055 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3559.

The product of its (nonzero) digits is 15750, while the sum is 35.

The square root of 191257055 is about 13829.5717576503. The cubic root of 191257055 is about 576.1547606510.

The spelling of 191257055 in words is "one hundred ninety-one million, two hundred fifty-seven thousand, fifty-five".