181285507147957 has 2 divisors, whose sum is σ = 181285507147958. Its totient is φ = 181285507147956.

The previous prime is 181285507147867. The next prime is 181285507148027. The reversal of 181285507147957 is 759741705582181.

It is an a-pointer prime, because the next prime (181285507148027) can be obtained adding 181285507147957 to its sum of digits (70).

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 172933256867281 + 8352250280676 = 13150409^2 + 2890026^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-181285507147957 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (181285507147757) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 90642753573978 + 90642753573979.

It is an arithmetic number, because the mean of its divisors is an integer number (90642753573979).

Almost surely, 2^{181285507147957} is an apocalyptic number.

It is an amenable number.

181285507147957 is a deficient number, since it is larger than the sum of its proper divisors (1).

181285507147957 is an equidigital number, since it uses as much as digits as its factorization.

181285507147957 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 197568000, while the sum is 70.

The spelling of 181285507147957 in words is "one hundred eighty-one trillion, two hundred eighty-five billion, five hundred seven million, one hundred forty-seven thousand, nine hundred fifty-seven".