40665997 has 4 divisors (see below), whose sum is σ = 41765116. Its totient is φ = 39566880.

The previous prime is 40665991. The next prime is 40666007. The reversal of 40665997 is 79956604.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 38266596 + 2399401 = 6186^2 + 1549^2 .

It is a cyclic number.

It is not a de Polignac number, because 40665997 - 2⁷ = 40665869 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (40665991) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 549504 + ... + 549577.

It is an arithmetic number, because the mean of its divisors is an integer number (10441279).

Almost surely, 2^40665997 is an apocalyptic number.

It is an amenable number.

40665997 is a deficient number, since it is larger than the sum of its proper divisors (1099119).

40665997 is a wasteful number, since it uses less digits than its factorization.

40665997 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1099118.

The product of its (nonzero) digits is 408240, while the sum is 46.

The square root of 40665997 is about 6376.9896502974. The cubic root of 40665997 is about 343.8828162468.

The spelling of 40665997 in words is "forty million, six hundred sixty-five thousand, nine hundred ninety-seven".