177242999981 has 2 divisors, whose sum is σ = 177242999982. Its totient is φ = 177242999980.

The previous prime is 177242999963. The next prime is 177243000047. The reversal of 177242999981 is 189999242771.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 118856010025 + 58386989956 = 344755^2 + 241634^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-177242999981 is a prime.

It is a super-2 number, since 2×177242999981² (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 (177242999911) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 88621499990 + 88621499991.

It is an arithmetic number, because the mean of its divisors is an integer number (88621499991).

Almost surely, 2^177242999981 is an apocalyptic number.

It is an amenable number.

177242999981 is a deficient number, since it is larger than the sum of its proper divisors (1).

177242999981 is an equidigital number, since it uses as much as digits as its factorization.

177242999981 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 41150592, while the sum is 68.

The spelling of 177242999981 in words is "one hundred seventy-seven billion, two hundred forty-two million, nine hundred ninety-nine thousand, nine hundred eighty-one".