1281978 has 24 divisors (see below), whose sum is σ = 2821728. Its totient is φ = 420552.

The previous prime is 1281971. The next prime is 1281979. The reversal of 1281978 is 8791821.

It is not an unprimeable number, because it can be changed into a prime (1281971) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 675 + ... + 1737.

It is an arithmetic number, because the mean of its divisors is an integer number (117572).

2^1281978 is an apocalyptic number.

1281978 is a gapful number since it is divisible by the number (18) formed by its first and last digit.

1281978 is an abundant number, since it is smaller than the sum of its proper divisors (1539750).

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

1281978 is a wasteful number, since it uses less digits than its factorization.

1281978 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1138 (or 1135 counting only the distinct ones).

The product of its digits is 8064, while the sum is 36.

The square root of 1281978 is about 1132.2446732045. The cubic root of 1281978 is about 108.6326041926.

The spelling of 1281978 in words is "one million, two hundred eighty-one thousand, nine hundred seventy-eight".