191431649 has 4 divisors (see below), whose sum is σ = 192339120. Its totient is φ = 190524180.

The previous prime is 191431627. The next prime is 191431661. The reversal of 191431649 is 946134191.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 191431649 - 2¹² = 191427553 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (191431619) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 453419 + ... + 453840.

It is an arithmetic number, because the mean of its divisors is an integer number (48084780).

Almost surely, 2^191431649 is an apocalyptic number.

It is an amenable number.

191431649 is a deficient number, since it is larger than the sum of its proper divisors (907471).

191431649 is an equidigital number, since it uses as much as digits as its factorization.

191431649 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 907470.

The product of its digits is 23328, while the sum is 38.

The square root of 191431649 is about 13835.8826606762. The cubic root of 191431649 is about 576.3300266389.

The spelling of 191431649 in words is "one hundred ninety-one million, four hundred thirty-one thousand, six hundred forty-nine".