7640235809 has 2 divisors, whose sum is σ = 7640235810. Its totient is φ = 7640235808.

The previous prime is 7640235773. The next prime is 7640235817. The reversal of 7640235809 is 9085320467.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 5565160000 + 2075075809 = 74600^2 + 45553^2 .

It is a cyclic number.

It is not a de Polignac number, because 7640235809 - 2²⁴ = 7623458593 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 7640235809.

It is not a weakly prime, because it can be changed into another prime (7640235409) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 3820117904 + 3820117905.

It is an arithmetic number, because the mean of its divisors is an integer number (3820117905).

Almost surely, 2^7640235809 is an apocalyptic number.

It is an amenable number.

7640235809 is a deficient number, since it is larger than the sum of its proper divisors (1).

7640235809 is an equidigital number, since it uses as much as digits as its factorization.

7640235809 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 362880, while the sum is 44.

The square root of 7640235809 is about 87408.4424354993. The cubic root of 7640235809 is about 1969.5586640514.

It can be divided in two parts, 76402 and 35809, that added together give a palindrome (112211).

The spelling of 7640235809 in words is "seven billion, six hundred forty million, two hundred thirty-five thousand, eight hundred nine".