40857639 has 8 divisors (see below), whose sum is σ = 54510960. Its totient is φ = 27221376.

The previous prime is 40857623. The next prime is 40857643. The reversal of 40857639 is 93675804.

It is a happy number.

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

It is not a de Polignac number, because 40857639 - 2⁴ = 40857623 is a prime.

It is a Smith number, since the sum of its digits (42) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a self number, because there is not a number n which added to its sum of digits gives 40857639.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (40857679) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 3189 + ... + 9585.

It is an arithmetic number, because the mean of its divisors is an integer number (6813870).

Almost surely, 2^40857639 is an apocalyptic number.

40857639 is a deficient number, since it is larger than the sum of its proper divisors (13653321).

40857639 is a wasteful number, since it uses less digits than its factorization.

40857639 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8529.

The product of its (nonzero) digits is 181440, while the sum is 42.

The square root of 40857639 is about 6391.9980444302. The cubic root of 40857639 is about 344.4221623193.

The spelling of 40857639 in words is "forty million, eight hundred fifty-seven thousand, six hundred thirty-nine".