40007857 has 4 divisors (see below), whose sum is σ = 40859136. Its totient is φ = 39156580.

The previous prime is 40007843. The next prime is 40007881. The reversal of 40007857 is 75870004.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 40007857 - 2⁷ = 40007729 is a prime.

It is a Smith number, since the sum of its digits (31) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (40007837) 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, 425569 + ... + 425662.

It is an arithmetic number, because the mean of its divisors is an integer number (10214784).

Almost surely, 2^40007857 is an apocalyptic number.

40007857 is a gapful number since it is divisible by the number (47) formed by its first and last digit.

It is an amenable number.

40007857 is a deficient number, since it is larger than the sum of its proper divisors (851279).

40007857 is an equidigital number, since it uses as much as digits as its factorization.

40007857 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 851278.

The product of its (nonzero) digits is 7840, while the sum is 31.

The square root of 40007857 is about 6325.1764402268. The cubic root of 40007857 is about 342.0175800044.

The spelling of 40007857 in words is "forty million, seven thousand, eight hundred fifty-seven".