157666189 has 2 divisors, whose sum is σ = 157666190. Its totient is φ = 157666188.

The previous prime is 157666181. The next prime is 157666241. The reversal of 157666189 is 981666751.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 127306089 + 30360100 = 11283^2 + 5510^2 .

It is a cyclic number.

It is not a de Polignac number, because 157666189 - 2³ = 157666181 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (157666181) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 78833094 + 78833095.

It is an arithmetic number, because the mean of its divisors is an integer number (78833095).

Almost surely, 2^157666189 is an apocalyptic number.

It is an amenable number.

157666189 is a deficient number, since it is larger than the sum of its proper divisors (1).

157666189 is an equidigital number, since it uses as much as digits as its factorization.

157666189 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 544320, while the sum is 49.

The square root of 157666189 is about 12556.5197805761. The cubic root of 157666189 is about 540.2310271177.

The spelling of 157666189 in words is "one hundred fifty-seven million, six hundred sixty-six thousand, one hundred eighty-nine".