1291840704 has 672 divisors, whose sum is σ = 5142585600. Its totient is φ = 313528320.

The previous prime is 1291840687. The next prime is 1291840741. The reversal of 1291840704 is 4070481921.

It is a tau number, because it is divible by the number of its divisors (672).

It is a super-2 number, since 2×1291840704² = 3337704809022431232, 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 95 ways as a sum of consecutive naturals, for example, 17696412 + ... + 17696484.

Almost surely, 2^1291840704 is an apocalyptic number.

1291840704 is a gapful number since it is divisible by the number (14) 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 1291840704, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2571292800).

1291840704 is an abundant number, since it is smaller than the sum of its proper divisors (3850744896).

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

1291840704 is a wasteful number, since it uses less digits than its factorization.

1291840704 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 138 (or 115 counting only the distinct ones).

The product of its (nonzero) digits is 16128, while the sum is 36.

The square root of 1291840704 is about 35942.1855762835. The cubic root of 1291840704 is about 1089.1047565976.

The spelling of 1291840704 in words is "one billion, two hundred ninety-one million, eight hundred forty thousand, seven hundred four".