1291879680 has 288 divisors, whose sum is σ = 5079454464. Its totient is φ = 272498688.

The previous prime is 1291879669. The next prime is 1291879697. The reversal of 1291879680 is 869781921.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 347592 + ... + 351288.

Almost surely, 2^1291879680 is an apocalyptic number.

1291879680 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 1291879680, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2539727232).

1291879680 is an abundant number, since it is smaller than the sum of its proper divisors (3787574784).

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

1291879680 is a wasteful number, since it uses less digits than its factorization.

1291879680 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3741 (or 3727 counting only the distinct ones).

The product of its (nonzero) digits is 435456, while the sum is 51.

The square root of 1291879680 is about 35942.7277762832. The cubic root of 1291879680 is about 1089.1157095786.

The spelling of 1291879680 in words is "one billion, two hundred ninety-one million, eight hundred seventy-nine thousand, six hundred eighty".