40569891 has 4 divisors (see below), whose sum is σ = 54093192. Its totient is φ = 27046592.

The previous prime is 40569887. The next prime is 40569911. The reversal of 40569891 is 19896504.

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

It is a cyclic number.

It is not a de Polignac number, because 40569891 - 2² = 40569887 is a prime.

It is not an unprimeable number, because it can be changed into a prime (40569091) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 6761646 + ... + 6761651.

It is an arithmetic number, because the mean of its divisors is an integer number (13523298).

Almost surely, 2^40569891 is an apocalyptic number.

40569891 is a deficient number, since it is larger than the sum of its proper divisors (13523301).

40569891 is a wasteful number, since it uses less digits than its factorization.

40569891 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 13523300.

The product of its (nonzero) digits is 77760, while the sum is 42.

The square root of 40569891 is about 6369.4498192544. The cubic root of 40569891 is about 343.6117030016.

The spelling of 40569891 in words is "forty million, five hundred sixty-nine thousand, eight hundred ninety-one".