191459212661 has 2 divisors, whose sum is σ = 191459212662. Its totient is φ = 191459212660.

The previous prime is 191459212657. The next prime is 191459212739. The reversal of 191459212661 is 166212954191.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 139068580561 + 52390632100 = 372919^2 + 228890^2 .

It is a cyclic number.

It is not a de Polignac number, because 191459212661 - 2² = 191459212657 is a prime.

It is a super-2 number, since 2×191459212661² (a number of 23 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (191459212631) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 95729606330 + 95729606331.

It is an arithmetic number, because the mean of its divisors is an integer number (95729606331).

Almost surely, 2^191459212661 is an apocalyptic number.

It is an amenable number.

191459212661 is a deficient number, since it is larger than the sum of its proper divisors (1).

191459212661 is an equidigital number, since it uses as much as digits as its factorization.

191459212661 is an evil number, because the sum of its binary digits is even.

The product of its digits is 233280, while the sum is 47.

The spelling of 191459212661 in words is "one hundred ninety-one billion, four hundred fifty-nine million, two hundred twelve thousand, six hundred sixty-one".