181887157 has 2 divisors, whose sum is σ = 181887158. Its totient is φ = 181887156.

The previous prime is 181887107. The next prime is 181887187. The reversal of 181887157 is 751788181.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 148084561 + 33802596 = 12169^2 + 5814^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-181887157 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (181887107) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 90943578 + 90943579.

It is an arithmetic number, because the mean of its divisors is an integer number (90943579).

Almost surely, 2^181887157 is an apocalyptic number.

It is an amenable number.

181887157 is a deficient number, since it is larger than the sum of its proper divisors (1).

181887157 is an equidigital number, since it uses as much as digits as its factorization.

181887157 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 125440, while the sum is 46.

The square root of 181887157 is about 13486.5546749346. The cubic root of 181887157 is about 566.5879644255.

The spelling of 181887157 in words is "one hundred eighty-one million, eight hundred eighty-seven thousand, one hundred fifty-seven".