183991738681 has 2 divisors, whose sum is σ = 183991738682. Its totient is φ = 183991738680.

The previous prime is 183991738597. The next prime is 183991738739. The reversal of 183991738681 is 186837199381.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 142815212281 + 41176526400 = 377909^2 + 202920^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-183991738681 is a prime.

It is a super-2 number, since 2×183991738681² (a number of 23 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (183991238681) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 91995869340 + 91995869341.

It is an arithmetic number, because the mean of its divisors is an integer number (91995869341).

Almost surely, 2^183991738681 is an apocalyptic number.

It is an amenable number.

183991738681 is a deficient number, since it is larger than the sum of its proper divisors (1).

183991738681 is an equidigital number, since it uses as much as digits as its factorization.

183991738681 is an evil number, because the sum of its binary digits is even.

The product of its digits is 15676416, while the sum is 64.

The spelling of 183991738681 in words is "one hundred eighty-three billion, nine hundred ninety-one million, seven hundred thirty-eight thousand, six hundred eighty-one".