165986357 has 2 divisors, whose sum is σ = 165986358. Its totient is φ = 165986356.

The previous prime is 165986291. The next prime is 165986363. The reversal of 165986357 is 753689561.

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., 144817156 + 21169201 = 12034^2 + 4601^2 .

It is a cyclic number.

It is not a de Polignac number, because 165986357 - 2¹² = 165982261 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (165986257) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 82993178 + 82993179.

It is an arithmetic number, because the mean of its divisors is an integer number (82993179).

Almost surely, 2^165986357 is an apocalyptic number.

It is an amenable number.

165986357 is a deficient number, since it is larger than the sum of its proper divisors (1).

165986357 is an equidigital number, since it uses as much as digits as its factorization.

165986357 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1360800, while the sum is 50.

The square root of 165986357 is about 12883.5692647651. The cubic root of 165986357 is about 549.5714093557.

The spelling of 165986357 in words is "one hundred sixty-five million, nine hundred eighty-six thousand, three hundred fifty-seven".