191408797 has 4 divisors (see below), whose sum is σ = 202668156. Its totient is φ = 180149440.

The previous prime is 191408773. The next prime is 191408813. The reversal of 191408797 is 797804191.

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

It can be written as a sum of positive squares in 2 ways, for example, as 147039876 + 44368921 = 12126^2 + 6661^2 .

It is a cyclic number.

It is not a de Polignac number, because 191408797 - 2¹⁹ = 190884509 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (191408297) 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, 5629654 + ... + 5629687.

It is an arithmetic number, because the mean of its divisors is an integer number (50667039).

Almost surely, 2^191408797 is an apocalyptic number.

191408797 is a gapful number since it is divisible by the number (17) formed by its first and last digit.

It is an amenable number.

191408797 is a deficient number, since it is larger than the sum of its proper divisors (11259359).

191408797 is a wasteful number, since it uses less digits than its factorization.

191408797 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11259358.

The product of its (nonzero) digits is 127008, while the sum is 46.

The square root of 191408797 is about 13835.0568123156. The cubic root of 191408797 is about 576.3070927477.

The spelling of 191408797 in words is "one hundred ninety-one million, four hundred eight thousand, seven hundred ninety-seven".