1291980 has 48 divisors (see below), whose sum is σ = 3687264. Its totient is φ = 337920.

The previous prime is 1291967. The next prime is 1291991. The reversal of 1291980 is 891921.

It is a Smith number, since the sum of its digits (30) coincides with the sum of the digits of its prime factors.

It is a Harshad number since it is a multiple of its sum of digits (30).

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 3484 + ... + 3836.

It is an arithmetic number, because the mean of its divisors is an integer number (76818).

2^1291980 is an apocalyptic number.

1291980 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 1291980, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1843632).

1291980 is an abundant number, since it is smaller than the sum of its proper divisors (2395284).

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

1291980 is a wasteful number, since it uses less digits than its factorization.

1291980 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 426 (or 424 counting only the distinct ones).

The product of its (nonzero) digits is 1296, while the sum is 30.

The square root of 1291980 is about 1136.6529813448. The cubic root of 1291980 is about 108.9143900351.

The spelling of 1291980 in words is "one million, two hundred ninety-one thousand, nine hundred eighty".