1279779660 has 36 divisors (see below), whose sum is σ = 3881998848. Its totient is φ = 341274528.

The previous prime is 1279779619. The next prime is 1279779661. The reversal of 1279779660 is 669779721.

It is a happy number.

It is a tau number, because it is divible by the number of its divisors (36).

It is a junction number, because it is equal to n+sod(n) for n = 1279779597 and 1279779606.

It is not an unprimeable number, because it can be changed into a prime (1279779661) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 3554764 + ... + 3555123.

Almost surely, 2^1279779660 is an apocalyptic number.

1279779660 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1279779660 is an abundant number, since it is smaller than the sum of its proper divisors (2602219188).

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

1279779660 is a wasteful number, since it uses less digits than its factorization.

1279779660 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7109902 (or 7109897 counting only the distinct ones).

The product of its (nonzero) digits is 2000376, while the sum is 54.

The square root of 1279779660 is about 35774.0081623516. The cubic root of 1279779660 is about 1085.7047415234.

The spelling of 1279779660 in words is "one billion, two hundred seventy-nine million, seven hundred seventy-nine thousand, six hundred sixty".