187618827661 has 2 divisors, whose sum is σ = 187618827662. Its totient is φ = 187618827660.

The previous prime is 187618827569. The next prime is 187618827703. The reversal of 187618827661 is 166728816781.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 184723742025 + 2895085636 = 429795^2 + 53806^2 .

It is a cyclic number.

It is not a de Polignac number, because 187618827661 - 2¹¹ = 187618825613 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 187618827661.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (187618827961) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 93809413830 + 93809413831.

It is an arithmetic number, because the mean of its divisors is an integer number (93809413831).

Almost surely, 2^187618827661 is an apocalyptic number.

It is an amenable number.

187618827661 is a deficient number, since it is larger than the sum of its proper divisors (1).

187618827661 is an equidigital number, since it uses as much as digits as its factorization.

187618827661 is an evil number, because the sum of its binary digits is even.

The product of its digits is 10838016, while the sum is 61.

The spelling of 187618827661 in words is "one hundred eighty-seven billion, six hundred eighteen million, eight hundred twenty-seven thousand, six hundred sixty-one".