1213421 has 4 divisors (see below), whose sum is σ = 1323744. Its totient is φ = 1103100.

The previous prime is 1213379. The next prime is 1213427. The reversal of 1213421 is 1243121.

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, and also an emirpimes, since its reverse is a distinct semiprime: 1243121 = 11 ⋅113011.

It is a cyclic number.

It is not a de Polignac number, because 1213421 - 2⁶ = 1213357 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 1213396 and 1213405.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1213427) 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, 55145 + ... + 55166.

It is an arithmetic number, because the mean of its divisors is an integer number (330936).

2^1213421 is an apocalyptic number.

1213421 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

1213421 is a deficient number, since it is larger than the sum of its proper divisors (110323).

1213421 is a wasteful number, since it uses less digits than its factorization.

1213421 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 110322.

The product of its digits is 48, while the sum is 14.

The square root of 1213421 is about 1101.5539024487. The cubic root of 1213421 is about 106.6605541202.

Adding to 1213421 its reverse (1243121), we get a palindrome (2456542).

The spelling of 1213421 in words is "one million, two hundred thirteen thousand, four hundred twenty-one".