1221319 has 4 divisors (see below), whose sum is σ = 1332360. Its totient is φ = 1110280.

The previous prime is 1221299. The next prime is 1221373. The reversal of 1221319 is 9131221.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 9131221 = 11 ⋅830111.

It is a cyclic number.

It is not a de Polignac number, because 1221319 - 2¹¹ = 1219271 is a prime.

It is a super-2 number, since 2×1221319² = 2983240199522, which contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 1221296 and 1221305.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1221379) 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, 55504 + ... + 55525.

It is an arithmetic number, because the mean of its divisors is an integer number (333090).

2^1221319 is an apocalyptic number.

1221319 is a deficient number, since it is larger than the sum of its proper divisors (111041).

1221319 is a wasteful number, since it uses less digits than its factorization.

1221319 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 111040.

The product of its digits is 108, while the sum is 19.

The square root of 1221319 is about 1105.1330236673. The cubic root of 1221319 is about 106.8914670886.

It can be divided in two parts, 1221 and 319, that added together give a triangular number (1540 = T₅₅).

The spelling of 1221319 in words is "one million, two hundred twenty-one thousand, three hundred nineteen".