191609651 has 2 divisors, whose sum is σ = 191609652. Its totient is φ = 191609650.

The previous prime is 191609603. The next prime is 191609653. The reversal of 191609651 is 156906191.

It is a happy number.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-191609651 is a prime.

Together with 191609653, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (191609653) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 95804825 + 95804826.

It is an arithmetic number, because the mean of its divisors is an integer number (95804826).

Almost surely, 2^191609651 is an apocalyptic number.

191609651 is a deficient number, since it is larger than the sum of its proper divisors (1).

191609651 is an equidigital number, since it uses as much as digits as its factorization.

191609651 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 14580, while the sum is 38.

The square root of 191609651 is about 13842.3137878030. The cubic root of 191609651 is about 576.5086040709.

The spelling of 191609651 in words is "one hundred ninety-one million, six hundred nine thousand, six hundred fifty-one".