1289427200 has 54 divisors (see below), whose sum is σ = 3191549634. Its totient is φ = 515768320.

The previous prime is 1289427199. The next prime is 1289427221. The reversal of 1289427200 is 27249821.

It can be written as a sum of positive squares in 3 ways, for example, as 1478656 + 1287948544 = 1216^2 + 35888^2 .

It is an unprimeable number.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 94337 + ... + 107136.

It is an arithmetic number, because the mean of its divisors is an integer number (59102771).

Almost surely, 2^1289427200 is an apocalyptic number.

1289427200 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1289427200 is an abundant number, since it is smaller than the sum of its proper divisors (1902122434).

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

1289427200 is an equidigital number, since it uses as much as digits as its factorization.

1289427200 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 201499 (or 201480 counting only the distinct ones).

The product of its (nonzero) digits is 16128, while the sum is 35.

The square root of 1289427200 is about 35908.5950713753. The cubic root of 1289427200 is about 1088.4260874372.

The spelling of 1289427200 in words is "one billion, two hundred eighty-nine million, four hundred twenty-seven thousand, two hundred".