181887585797 has 2 divisors, whose sum is σ = 181887585798. Its totient is φ = 181887585796.

The previous prime is 181887585757. The next prime is 181887585833. The reversal of 181887585797 is 797585788181.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 180076317316 + 1811268481 = 424354^2 + 42559^2 .

It is a cyclic number.

It is not a de Polignac number, because 181887585797 - 2¹⁰ = 181887584773 is a prime.

It is a super-2 number, since 2×181887585797² (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 (181887585757) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 90943792898 + 90943792899.

It is an arithmetic number, because the mean of its divisors is an integer number (90943792899).

Almost surely, 2^181887585797 is an apocalyptic number.

It is an amenable number.

181887585797 is a deficient number, since it is larger than the sum of its proper divisors (1).

181887585797 is an equidigital number, since it uses as much as digits as its factorization.

181887585797 is an evil number, because the sum of its binary digits is even.

The product of its digits is 316108800, while the sum is 74.

The spelling of 181887585797 in words is "one hundred eighty-one billion, eight hundred eighty-seven million, five hundred eighty-five thousand, seven hundred ninety-seven".