1291140 has 60 divisors (see below), whose sum is σ = 4055436. Its totient is φ = 343872.

The previous prime is 1291139. The next prime is 1291153. The reversal of 1291140 is 411921.

It can be written as a sum of positive squares in 2 ways, for example, as 544644 + 746496 = 738^2 + 864^2 .

It is a tau number, because it is divible by the number of its divisors (60).

It is a Harshad number since it is a multiple of its sum of digits (18).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 19 ways as a sum of consecutive naturals, for example, 1222 + ... + 2018.

2^1291140 is an apocalyptic number.

1291140 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 1291140, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2027718).

1291140 is an abundant number, since it is smaller than the sum of its proper divisors (2764296).

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

1291140 is a wasteful number, since it uses less digits than its factorization.

1291140 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 818 (or 807 counting only the distinct ones).

The product of its (nonzero) digits is 72, while the sum is 18.

The square root of 1291140 is about 1136.2834153502. The cubic root of 1291140 is about 108.8907808146.

It can be divided in two parts, 1291 and 140, that added together give a triangular number (1431 = T₅₃).

The spelling of 1291140 in words is "one million, two hundred ninety-one thousand, one hundred forty".