1279881280 has 28 divisors (see below), whose sum is σ = 3047718060. Its totient is φ = 511952384.

The previous prime is 1279881271. The next prime is 1279881289. The reversal of 1279881280 is 821889721.

It is an interprime number because it is at equal distance from previous prime (1279881271) and next prime (1279881289).

It can be written as a sum of positive squares in 2 ways, for example, as 178703424 + 1101177856 = 13368^2 + 33184^2 .

It is a self number, because there is not a number n which added to its sum of digits gives 1279881280.

It is not an unprimeable number, because it can be changed into a prime (1279881289) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1999495 + ... + 2000134.

Almost surely, 2^1279881280 is an apocalyptic number.

1279881280 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1279881280 is an abundant number, since it is smaller than the sum of its proper divisors (1767836780).

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

1279881280 is an equidigital number, since it uses as much as digits as its factorization.

1279881280 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3999646 (or 3999636 counting only the distinct ones).

The product of its (nonzero) digits is 129024, while the sum is 46.

The square root of 1279881280 is about 35775.4284390837. The cubic root of 1279881280 is about 1085.7334773022.

The spelling of 1279881280 in words is "one billion, two hundred seventy-nine million, eight hundred eighty-one thousand, two hundred eighty".