190691591 has 4 divisors (see below), whose sum is σ = 192147384. Its totient is φ = 189235800.

The previous prime is 190691573. The next prime is 190691593. The reversal of 190691591 is 195196091.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 190691591 - 2¹⁰ = 190690567 is a prime.

It is a super-2 number, since 2×190691591² = 72726565756222562, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (190691593) 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, 727700 + ... + 727961.

It is an arithmetic number, because the mean of its divisors is an integer number (48036846).

Almost surely, 2^190691591 is an apocalyptic number.

190691591 is a deficient number, since it is larger than the sum of its proper divisors (1455793).

190691591 is a wasteful number, since it uses less digits than its factorization.

190691591 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1455792.

The product of its (nonzero) digits is 21870, while the sum is 41.

The square root of 190691591 is about 13809.1126072605. The cubic root of 190691591 is about 575.5863870523.

The spelling of 190691591 in words is "one hundred ninety million, six hundred ninety-one thousand, five hundred ninety-one".