40409257 has 12 divisors (see below), whose sum is σ = 48743616. Its totient is φ = 32811480.

The previous prime is 40409249. The next prime is 40409263. The reversal of 40409257 is 75290404.

It is not a de Polignac number, because 40409257 - 2³ = 40409249 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (40403257) 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 11 ways as a sum of consecutive naturals, for example, 5469 + ... + 10522.

It is an arithmetic number, because the mean of its divisors is an integer number (4061968).

Almost surely, 2^40409257 is an apocalyptic number.

It is an amenable number.

40409257 is a deficient number, since it is larger than the sum of its proper divisors (8334359).

40409257 is a wasteful number, since it uses less digits than its factorization.

40409257 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 16036 (or 16017 counting only the distinct ones).

The product of its (nonzero) digits is 10080, while the sum is 31.

The square root of 40409257 is about 6356.8275892933. The cubic root of 40409257 is about 343.1575999740.

The spelling of 40409257 in words is "forty million, four hundred nine thousand, two hundred fifty-seven".