191651387101 has 2 divisors, whose sum is σ = 191651387102. Its totient is φ = 191651387100.

The previous prime is 191651387009. The next prime is 191651387107. The reversal of 191651387101 is 101783156191.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 169827234201 + 21824152900 = 412101^2 + 147730^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-191651387101 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (191651387107) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 95825693550 + 95825693551.

It is an arithmetic number, because the mean of its divisors is an integer number (95825693551).

Almost surely, 2^191651387101 is an apocalyptic number.

It is an amenable number.

191651387101 is a deficient number, since it is larger than the sum of its proper divisors (1).

191651387101 is an equidigital number, since it uses as much as digits as its factorization.

191651387101 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 45360, while the sum is 43.

The spelling of 191651387101 in words is "one hundred ninety-one billion, six hundred fifty-one million, three hundred eighty-seven thousand, one hundred one".