1278121 has 4 divisors (see below), whose sum is σ = 1376452. Its totient is φ = 1179792.

The previous prime is 1278113. The next prime is 1278131. The reversal of 1278121 is 1218721.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 440896 + 837225 = 664^2 + 915^2 .

It is a cyclic number.

It is not a de Polignac number, because 1278121 - 2³ = 1278113 is a prime.

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

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 1278092 and 1278101.

It is not an unprimeable number, because it can be changed into a prime (1278131) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 49146 + ... + 49171.

It is an arithmetic number, because the mean of its divisors is an integer number (344113).

2^1278121 is an apocalyptic number.

It is an amenable number.

1278121 is a deficient number, since it is larger than the sum of its proper divisors (98331).

1278121 is an equidigital number, since it uses as much as digits as its factorization.

1278121 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 98330.

The product of its digits is 224, while the sum is 22.

The square root of 1278121 is about 1130.5401363950. The cubic root of 1278121 is about 108.5235495755.

The spelling of 1278121 in words is "one million, two hundred seventy-eight thousand, one hundred twenty-one".