1321403320 has 64 divisors (see below), whose sum is σ = 3002896800. Its totient is φ = 523307520.

The previous prime is 1321403269. The next prime is 1321403323. The reversal of 1321403320 is 233041231.

It is a super-2 number, since 2×1321403320² = 3492213468214044800, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1321403323) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 2442250 + ... + 2442790.

Almost surely, 2^1321403320 is an apocalyptic number.

1321403320 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1321403320 is an abundant number, since it is smaller than the sum of its proper divisors (1681493480).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

1321403320 is a wasteful number, since it uses less digits than its factorization.

1321403320 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1048 (or 1044 counting only the distinct ones).

The product of its (nonzero) digits is 432, while the sum is 19.

The square root of 1321403320 is about 36351.1116748855. Note that the first 3 decimals coincide. The cubic root of 1321403320 is about 1097.3499070900.

Adding to 1321403320 its reverse (233041231), we get a palindrome (1554444551).

It can be divided in two parts, 132140 and 3320, that added together give a triangular number (135460 = T₅₂₀).

The spelling of 1321403320 in words is "one billion, three hundred twenty-one million, four hundred three thousand, three hundred twenty".