1247428220 has 48 divisors (see below), whose sum is σ = 2709977088. Its totient is φ = 481826880.

The previous prime is 1247428219. The next prime is 1247428279. The reversal of 1247428220 is 228247421.

It is a congruent number.

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 15 ways as a sum of consecutive naturals, for example, 322337 + ... + 326183.

It is an arithmetic number, because the mean of its divisors is an integer number (56457856).

Almost surely, 2^1247428220 is an apocalyptic number.

1247428220 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1247428220, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1354988544).

1247428220 is an abundant number, since it is smaller than the sum of its proper divisors (1462548868).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

1247428220 is a wasteful number, since it uses less digits than its factorization.

1247428220 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4410 (or 4408 counting only the distinct ones).

The product of its (nonzero) digits is 14336, while the sum is 32.

The square root of 1247428220 is about 35318.9498711386. The cubic root of 1247428220 is about 1076.4780735126.

The spelling of 1247428220 in words is "one billion, two hundred forty-seven million, four hundred twenty-eight thousand, two hundred twenty".