1278945 has 24 divisors (see below), whose sum is σ = 2247336. Its totient is φ = 672768.

The previous prime is 1278911. The next prime is 1278983. The reversal of 1278945 is 5498721.

It can be written as a sum of positive squares in 4 ways, for example, as 374544 + 904401 = 612^2 + 951^2 .

It is not a de Polignac number, because 1278945 - 2⁶ = 1278881 is a prime.

It is an alternating number because its digits alternate between odd and even.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 4219 + ... + 4511.

It is an arithmetic number, because the mean of its divisors is an integer number (93639).

2^1278945 is an apocalyptic number.

1278945 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

1278945 is a deficient number, since it is larger than the sum of its proper divisors (968391).

1278945 is a wasteful number, since it uses less digits than its factorization.

1278945 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 401 (or 398 counting only the distinct ones).

The product of its digits is 20160, while the sum is 36.

The square root of 1278945 is about 1130.9045052523. The cubic root of 1278945 is about 108.5468661459.

The spelling of 1278945 in words is "one million, two hundred seventy-eight thousand, nine hundred forty-five".