165954981 has 8 divisors (see below), whose sum is σ = 221392000. Its totient is φ = 110577312.

The previous prime is 165954961. The next prime is 165954989. The reversal of 165954981 is 189459561.

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

It is not a de Polignac number, because 165954981 - 2⁹ = 165954469 is a prime.

It is a super-2 number, since 2×165954981² = 55082111437420722, 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 165954981.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (165954989) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 7840 + ... + 19833.

It is an arithmetic number, because the mean of its divisors is an integer number (27674000).

Almost surely, 2^165954981 is an apocalyptic number.

It is an amenable number.

165954981 is a deficient number, since it is larger than the sum of its proper divisors (55437019).

165954981 is a wasteful number, since it uses less digits than its factorization.

165954981 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 29675.

The product of its digits is 388800, while the sum is 48.

The square root of 165954981 is about 12882.3515322320. The cubic root of 165954981 is about 549.5367791217.

The spelling of 165954981 in words is "one hundred sixty-five million, nine hundred fifty-four thousand, nine hundred eighty-one".