1247787428 has 12 divisors (see below), whose sum is σ = 2192126412. Its totient is φ = 621465600.

The previous prime is 1247787407. The next prime is 1247787439. The reversal of 1247787428 is 8247877421.

It can be written as a sum of positive squares in 2 ways, for example, as 1235663104 + 12124324 = 35152^2 + 3482^2 .

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 605873 + ... + 607928.

It is an arithmetic number, because the mean of its divisors is an integer number (182677201).

Almost surely, 2^1247787428 is an apocalyptic number.

It is an amenable number.

1247787428 is a deficient number, since it is larger than the sum of its proper divisors (944338984).

1247787428 is a wasteful number, since it uses less digits than its factorization.

1247787428 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1214062 (or 1214060 counting only the distinct ones).

The product of its digits is 1404928, while the sum is 50.

The square root of 1247787428 is about 35324.0347072641. The cubic root of 1247787428 is about 1076.5813907268.

The spelling of 1247787428 in words is "one billion, two hundred forty-seven million, seven hundred eighty-seven thousand, four hundred twenty-eight".