7748979509 has 2 divisors, whose sum is σ = 7748979510. Its totient is φ = 7748979508.

The previous prime is 7748979487. The next prime is 7748979569. The reversal of 7748979509 is 9059798477.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 7661500900 + 87478609 = 87530^2 + 9353^2 .

It is a cyclic number.

It is not a de Polignac number, because 7748979509 - 2²⁰ = 7747930933 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (7748979569) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 3874489754 + 3874489755.

It is an arithmetic number, because the mean of its divisors is an integer number (3874489755).

Almost surely, 2^7748979509 is an apocalyptic number.

It is an amenable number.

7748979509 is a deficient number, since it is larger than the sum of its proper divisors (1).

7748979509 is an equidigital number, since it uses as much as digits as its factorization.

7748979509 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 40007520, while the sum is 65.

The square root of 7748979509 is about 88028.2881180817. The cubic root of 7748979509 is about 1978.8589409680.

The spelling of 7748979509 in words is "seven billion, seven hundred forty-eight million, nine hundred seventy-nine thousand, five hundred nine".