1378421 has 4 divisors (see below), whose sum is σ = 1503744. Its totient is φ = 1253100.

The previous prime is 1378397. The next prime is 1378427. The reversal of 1378421 is 1248731.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 1378421 - 2¹⁸ = 1116277 is a prime.

It is an Ulam number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1378427) 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, 62645 + ... + 62666.

It is an arithmetic number, because the mean of its divisors is an integer number (375936).

2^1378421 is an apocalyptic number.

1378421 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

1378421 is a deficient number, since it is larger than the sum of its proper divisors (125323).

1378421 is a wasteful number, since it uses less digits than its factorization.

1378421 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 125322.

The product of its digits is 1344, while the sum is 26.

The square root of 1378421 is about 1174.0617530607. The cubic root of 1378421 is about 111.2911491931.

It can be divided in two parts, 137 and 8421, that added together give a palindrome (8558).

The spelling of 1378421 in words is "one million, three hundred seventy-eight thousand, four hundred twenty-one".