1390878 has 32 divisors (see below), whose sum is σ = 3168000. Its totient is φ = 452088.

The previous prime is 1390859. The next prime is 1390891. The reversal of 1390878 is 8780931.

It is a super-2 number, since 2×1390878² = 3869083221768, which contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 2023 + ... + 2621.

It is an arithmetic number, because the mean of its divisors is an integer number (99000).

2^1390878 is an apocalyptic number.

1390878 is a gapful number since it is divisible by the number (18) formed by its first and last digit.

It is a practical number, because each smaller number is the sum of distinct divisors of 1390878, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1584000).

1390878 is an abundant number, since it is smaller than the sum of its proper divisors (1777122).

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

1390878 is a wasteful number, since it uses less digits than its factorization.

1390878 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 653 (or 647 counting only the distinct ones).

The product of its (nonzero) digits is 12096, while the sum is 36.

The square root of 1390878 is about 1179.3549084139. The cubic root of 1390878 is about 111.6253960009.

The spelling of 1390878 in words is "one million, three hundred ninety thousand, eight hundred seventy-eight".