1291630340 has 192 divisors, whose sum is σ = 3674764800. Its totient is φ = 368271360.

The previous prime is 1291630321. The next prime is 1291630357. The reversal of 1291630340 is 430361921.

It is an unprimeable number.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 2982764 + ... + 2983196.

It is an arithmetic number, because the mean of its divisors is an integer number (19139400).

Almost surely, 2^1291630340 is an apocalyptic number.

1291630340 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 1291630340, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1837382400).

1291630340 is an abundant number, since it is smaller than the sum of its proper divisors (2383134460).

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

1291630340 is a wasteful number, since it uses less digits than its factorization.

1291630340 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 622 (or 620 counting only the distinct ones).

The product of its (nonzero) digits is 3888, while the sum is 29.

The square root of 1291630340 is about 35939.2590352111. The cubic root of 1291630340 is about 1089.0456365969.

The spelling of 1291630340 in words is "one billion, two hundred ninety-one million, six hundred thirty thousand, three hundred forty".