180991839881 has 2 divisors, whose sum is σ = 180991839882. Its totient is φ = 180991839880.

The previous prime is 180991839851. The next prime is 180991839893. The reversal of 180991839881 is 188938199081.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 131359129225 + 49632710656 = 362435^2 + 222784^2 .

It is a cyclic number.

It is not a de Polignac number, because 180991839881 - 2³⁴ = 163811970697 is a prime.

It is a super-2 number, since 2×180991839881² (a number of 23 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (180991839841) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 90495919940 + 90495919941.

It is an arithmetic number, because the mean of its divisors is an integer number (90495919941).

Almost surely, 2^180991839881 is an apocalyptic number.

It is an amenable number.

180991839881 is a deficient number, since it is larger than the sum of its proper divisors (1).

180991839881 is an equidigital number, since it uses as much as digits as its factorization.

180991839881 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 8957952, while the sum is 65.

The spelling of 180991839881 in words is "one hundred eighty billion, nine hundred ninety-one million, eight hundred thirty-nine thousand, eight hundred eighty-one".