165971969 has 8 divisors (see below), whose sum is σ = 177960960. Its totient is φ = 154230336.

The previous prime is 165971963. The next prime is 165972019. The reversal of 165971969 is 969179561.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 165971969 - 2²⁴ = 149194753 is a prime.

It is a super-2 number, since 2×165971969² = 55093388987473922, which contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 165971969.

It is not an unprimeable number, because it can be changed into a prime (165971963) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 60449 + ... + 63134.

It is an arithmetic number, because the mean of its divisors is an integer number (22245120).

Almost surely, 2^165971969 is an apocalyptic number.

It is an amenable number.

165971969 is a deficient number, since it is larger than the sum of its proper divisors (11988991).

165971969 is a wasteful number, since it uses less digits than its factorization.

165971969 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 123679.

The product of its digits is 918540, while the sum is 53.

The square root of 165971969 is about 12883.0108670295. The cubic root of 165971969 is about 549.5555296130. Note that the first 4 decimals are identical.

The spelling of 165971969 in words is "one hundred sixty-five million, nine hundred seventy-one thousand, nine hundred sixty-nine".