1279111680 has 720 divisors, whose sum is σ = 5676225984. Its totient is φ = 263208960.

The previous prime is 1279111679. The next prime is 1279111753. The reversal of 1279111680 is 861119721.

It is a tau number, because it is divible by the number of its divisors (720).

It is a super-2 number, since 2×1279111680² = 3272253379824844800, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 71 ways as a sum of consecutive naturals, for example, 12418509 + ... + 12418611.

Almost surely, 2^1279111680 is an apocalyptic number.

1279111680 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 1279111680, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2838112992).

1279111680 is an abundant number, since it is smaller than the sum of its proper divisors (4397114304).

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

1279111680 is a wasteful number, since it uses less digits than its factorization.

1279111680 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 157 (or 131 counting only the distinct ones).

The product of its (nonzero) digits is 6048, while the sum is 36.

The square root of 1279111680 is about 35764.6708358961. The cubic root of 1279111680 is about 1085.5158144005.

The spelling of 1279111680 in words is "one billion, two hundred seventy-nine million, one hundred eleven thousand, six hundred eighty".