7640813 has 4 divisors (see below), whose sum is σ = 7652160. Its totient is φ = 7629468.

The previous prime is 7640777. The next prime is 7640821. The reversal of 7640813 is 3180467.

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, and also an emirpimes, since its reverse is a distinct semiprime: 3180467 = 19 ⋅167393.

It is a cyclic number.

It is not a de Polignac number, because 7640813 - 2⁶ = 7640749 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 (7640873) 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, 4595 + ... + 6032.

It is an arithmetic number, because the mean of its divisors is an integer number (1913040).

Almost surely, 2^7640813 is an apocalyptic number.

It is an amenable number.

7640813 is a deficient number, since it is larger than the sum of its proper divisors (11347).

7640813 is a wasteful number, since it uses less digits than its factorization.

7640813 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 11346.

The product of its (nonzero) digits is 4032, while the sum is 29.

The square root of 7640813 is about 2764.2020548433. The cubic root of 7640813 is about 196.9608260379.

The spelling of 7640813 in words is "seven million, six hundred forty thousand, eight hundred thirteen".