1321406520 has 96 divisors (see below), whose sum is σ = 4611459600. Its totient is φ = 302034432.

The previous prime is 1321406501. The next prime is 1321406521. The reversal of 1321406520 is 256041231.

It is a super-2 number, since 2×1321406520² = 3492230382197020800, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (24).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1321406521) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 106485 + ... + 118244.

Almost surely, 2^1321406520 is an apocalyptic number.

1321406520 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1321406520 is an abundant number, since it is smaller than the sum of its proper divisors (3290053080).

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

1321406520 is a wasteful number, since it uses less digits than its factorization.

1321406520 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 224757 (or 224746 counting only the distinct ones).

The product of its (nonzero) digits is 1440, while the sum is 24.

The square root of 1321406520 is about 36351.1556900190. The cubic root of 1321406520 is about 1097.3507928949.

Adding to 1321406520 its reverse (256041231), we get a palindrome (1577447751).

The spelling of 1321406520 in words is "one billion, three hundred twenty-one million, four hundred six thousand, five hundred twenty".