1378261 has 4 divisors (see below), whose sum is σ = 1390572. Its totient is φ = 1365952.

The previous prime is 1378253. The next prime is 1378271. The reversal of 1378261 is 1628731.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 1628731 = 13 ⋅125287.

It can be written as a sum of positive squares in 2 ways, for example, as 398161 + 980100 = 631^2 + 990^2 .

It is a cyclic number.

It is not a de Polignac number, because 1378261 - 2³ = 1378253 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1378231) by changing a digit.

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 3 ways as a sum of consecutive naturals, for example, 5986 + ... + 6211.

It is an arithmetic number, because the mean of its divisors is an integer number (347643).

2^1378261 is an apocalyptic number.

It is an amenable number.

1378261 is a deficient number, since it is larger than the sum of its proper divisors (12311).

1378261 is a wasteful number, since it uses less digits than its factorization.

1378261 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 12310.

The product of its digits is 2016, while the sum is 28.

The square root of 1378261 is about 1173.9936115669. The cubic root of 1378261 is about 111.2868429923.

The spelling of 1378261 in words is "one million, three hundred seventy-eight thousand, two hundred sixty-one".