7728939 has 10 divisors (see below), whose sum is σ = 11545820. Its totient is φ = 5152572.

The previous prime is 7728923. The next prime is 7728983. The reversal of 7728939 is 9398277.

It is not a de Polignac number, because 7728939 - 2⁴ = 7728923 is a prime.

It is an Ulam number.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 7728894 and 7728903.

It is not an unprimeable number, because it can be changed into a prime (7728139) by changing a digit.

It is a polite number, since it can be written in 9 ways as a sum of consecutive naturals, for example, 47629 + ... + 47790.

It is an arithmetic number, because the mean of its divisors is an integer number (1154582).

Almost surely, 2^7728939 is an apocalyptic number.

7728939 is a deficient number, since it is larger than the sum of its proper divisors (3816881).

7728939 is an equidigital number, since it uses as much as digits as its factorization.

7728939 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 95431 (or 95422 counting only the distinct ones).

The product of its digits is 190512, while the sum is 45.

The square root of 7728939 is about 2780.0969407558. The cubic root of 7728939 is about 197.7151551541.

The spelling of 7728939 in words is "seven million, seven hundred twenty-eight thousand, nine hundred thirty-nine".