1291749684 has 24 divisors (see below), whose sum is σ = 3025212288. Its totient is φ = 428993280.

The previous prime is 1291749659. The next prime is 1291749707. The reversal of 1291749684 is 4869471921.

It is a super-2 number, since 2×1291749684² = 3337234492228199712, which contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 195357 + ... + 201860.

It is an arithmetic number, because the mean of its divisors is an integer number (126050512).

Almost surely, 2^1291749684 is an apocalyptic number.

It is an amenable number.

1291749684 is an abundant number, since it is smaller than the sum of its proper divisors (1733462604).

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

1291749684 is a wasteful number, since it uses less digits than its factorization.

1291749684 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 397495 (or 397493 counting only the distinct ones).

The product of its digits is 870912, while the sum is 51.

The square root of 1291749684 is about 35940.9193538507. The cubic root of 1291749684 is about 1089.0791774265.

The spelling of 1291749684 in words is "one billion, two hundred ninety-one million, seven hundred forty-nine thousand, six hundred eighty-four".