1213421331 has 4 divisors (see below), whose sum is σ = 1617895112. Its totient is φ = 808947552.

The previous prime is 1213421329. The next prime is 1213421357. The reversal of 1213421331 is 1331243121.

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

It is not a de Polignac number, because 1213421331 - 2¹ = 1213421329 is a prime.

It is a super-2 number, since 2×1213421331² = 2944782653051623122, 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 = 1213421298 and 1213421307.

It is not an unprimeable number, because it can be changed into a prime (1213421381) 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, 202236886 + ... + 202236891.

It is an arithmetic number, because the mean of its divisors is an integer number (404473778).

Almost surely, 2^1213421331 is an apocalyptic number.

1213421331 is a deficient number, since it is larger than the sum of its proper divisors (404473781).

1213421331 is an equidigital number, since it uses as much as digits as its factorization.

1213421331 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 404473780.

The product of its digits is 432, while the sum is 21.

The square root of 1213421331 is about 34834.1977229274. The cubic root of 1213421331 is about 1066.6056381859.

Adding to 1213421331 its reverse (1331243121), we get a palindrome (2544664452).

The spelling of 1213421331 in words is "one billion, two hundred thirteen million, four hundred twenty-one thousand, three hundred thirty-one".