28724640772 has 12 divisors (see below), whose sum is σ = 50282873676. Its totient is φ = 14358105440.

The previous prime is 28724640761. The next prime is 28724640803. The reversal of 28724640772 is 27704642782.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 11478122496 + 17246518276 = 107136^2 + 131326^2 .

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1038379 + ... + 1065682.

It is an arithmetic number, because the mean of its divisors is an integer number (4190239473).

Almost surely, 2^28724640772 is an apocalyptic number.

It is an amenable number.

28724640772 is a deficient number, since it is larger than the sum of its proper divisors (21558232904).

28724640772 is a wasteful number, since it uses less digits than its factorization.

28724640772 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2107478 (or 2107476 counting only the distinct ones).

The product of its (nonzero) digits is 2107392, while the sum is 49.

The spelling of 28724640772 in words is "twenty-eight billion, seven hundred twenty-four million, six hundred forty thousand, seven hundred seventy-two".