1321531123 has 4 divisors (see below), whose sum is σ = 1441670328. Its totient is φ = 1201391920.

The previous prime is 1321531103. The next prime is 1321531153. The reversal of 1321531123 is 3211351231.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 3211351231 = 11 ⋅291941021.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1321531123 is a prime.

It is a super-2 number, since 2×1321531123² = 3492889018115282258, 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 = 1321531094 and 1321531103.

It is not an unprimeable number, because it can be changed into a prime (1321531103) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 60069586 + ... + 60069607.

It is an arithmetic number, because the mean of its divisors is an integer number (360417582).

Almost surely, 2^1321531123 is an apocalyptic number.

1321531123 is a deficient number, since it is larger than the sum of its proper divisors (120139205).

1321531123 is a wasteful number, since it uses less digits than its factorization.

1321531123 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 120139204.

The product of its digits is 540, while the sum is 22.

The square root of 1321531123 is about 36352.8695291032. The cubic root of 1321531123 is about 1097.3852836443.

Adding to 1321531123 its reverse (3211351231), we get a palindrome (4532882354).

The spelling of 1321531123 in words is "one billion, three hundred twenty-one million, five hundred thirty-one thousand, one hundred twenty-three".