165964397 has 2 divisors, whose sum is σ = 165964398. Its totient is φ = 165964396.

The previous prime is 165964369. The next prime is 165964439. The reversal of 165964397 is 793469561.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 158407396 + 7557001 = 12586^2 + 2749^2 .

It is an emirp because it is prime and its reverse (793469561) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 165964397 - 2⁶ = 165964333 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (165964327) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 82982198 + 82982199.

It is an arithmetic number, because the mean of its divisors is an integer number (82982199).

Almost surely, 2^165964397 is an apocalyptic number.

It is an amenable number.

165964397 is a deficient number, since it is larger than the sum of its proper divisors (1).

165964397 is an equidigital number, since it uses as much as digits as its factorization.

165964397 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 1224720, while the sum is 50.

The square root of 165964397 is about 12882.7169882754. The cubic root of 165964397 is about 549.5471721822.

The spelling of 165964397 in words is "one hundred sixty-five million, nine hundred sixty-four thousand, three hundred ninety-seven".