40687813 has 4 divisors (see below), whose sum is σ = 40730688. Its totient is φ = 40644940.

The previous prime is 40687771. The next prime is 40687859. The reversal of 40687813 is 31878604.

It is a happy number.

40687813 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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 40687813 - 2⁹ = 40687301 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 (40681813) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 19981 + ... + 21922.

It is an arithmetic number, because the mean of its divisors is an integer number (10182672).

Almost surely, 2^40687813 is an apocalyptic number.

It is an amenable number.

40687813 is a deficient number, since it is larger than the sum of its proper divisors (42875).

40687813 is an equidigital number, since it uses as much as digits as its factorization.

40687813 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 42874.

The product of its (nonzero) digits is 32256, while the sum is 37.

The square root of 40687813 is about 6378.6999459137. The cubic root of 40687813 is about 343.9442992787.

It can be divided in two parts, 4068 and 7813, that added together give a square (11881 = 109²).

The spelling of 40687813 in words is "forty million, six hundred eighty-seven thousand, eight hundred thirteen".