201959686661 has 2 divisors, whose sum is σ = 201959686662. Its totient is φ = 201959686660.

The previous prime is 201959686583. The next prime is 201959686681. The reversal of 201959686661 is 166686959102.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 198782222500 + 3177464161 = 445850^2 + 56369^2 .

It is a cyclic number.

It is not a de Polignac number, because 201959686661 - 2²⁶ = 201892577797 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 201959686661.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (201959686681) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 100979843330 + 100979843331.

It is an arithmetic number, because the mean of its divisors is an integer number (100979843331).

Almost surely, 2^201959686661 is an apocalyptic number.

It is an amenable number.

201959686661 is a deficient number, since it is larger than the sum of its proper divisors (1).

201959686661 is an equidigital number, since it uses as much as digits as its factorization.

201959686661 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 8398080, while the sum is 59.

The spelling of 201959686661 in words is "two hundred one billion, nine hundred fifty-nine million, six hundred eighty-six thousand, six hundred sixty-one".