1278990 has 40 divisors (see below), whose sum is σ = 3441240. Its totient is φ = 340848.

The previous prime is 1278983. The next prime is 1278997. The reversal of 1278990 is 998721.

It is a happy number.

It is an interprime number because it is at equal distance from previous prime (1278983) and next prime (1278997).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1278997) by changing a digit.

It is a polite number, since it can be written in 19 ways as a sum of consecutive naturals, for example, 21 + ... + 1599.

It is an arithmetic number, because the mean of its divisors is an integer number (86031).

2^1278990 is an apocalyptic number.

1278990 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is a practical number, because each smaller number is the sum of distinct divisors of 1278990, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1720620).

1278990 is an abundant number, since it is smaller than the sum of its proper divisors (2162250).

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

1278990 is a wasteful number, since it uses less digits than its factorization.

1278990 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1598 (or 1589 counting only the distinct ones).

The product of its (nonzero) digits is 9072, while the sum is 36.

The square root of 1278990 is about 1130.9244006564. The cubic root of 1278990 is about 108.5481392138.

The spelling of 1278990 in words is "one million, two hundred seventy-eight thousand, nine hundred ninety".