40991165 has 16 divisors (see below), whose sum is σ = 52581312. Its totient is φ = 30568704.

The previous prime is 40991149. The next prime is 40991173. The reversal of 40991165 is 56119904.

It is a cyclic number.

It is not a de Polignac number, because 40991165 - 2⁴ = 40991149 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 6842 + ... + 11348.

It is an arithmetic number, because the mean of its divisors is an integer number (3286332).

Almost surely, 2^40991165 is an apocalyptic number.

It is an amenable number.

40991165 is a deficient number, since it is larger than the sum of its proper divisors (11590147).

40991165 is a wasteful number, since it uses less digits than its factorization.

40991165 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4636.

The product of its (nonzero) digits is 9720, while the sum is 35.

The square root of 40991165 is about 6402.4343026696. The cubic root of 40991165 is about 344.7969539668.

The spelling of 40991165 in words is "forty million, nine hundred ninety-one thousand, one hundred sixty-five".