1321520000 has 80 divisors (see below), whose sum is σ = 3290040600. Its totient is φ = 528576000.

The previous prime is 1321519909. The next prime is 1321520003. The reversal of 1321520000 is 251231.

It is a happy number.

It is a tau number, because it is divible by the number of its divisors (80).

It is a super-2 number, since 2×1321520000² = 3492830220800000000, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1321520003) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 9 ways as a sum of consecutive naturals, for example, 71741 + ... + 88259.

Almost surely, 2^1321520000 is an apocalyptic number.

1321520000 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1321520000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1645020300).

1321520000 is an abundant number, since it is smaller than the sum of its proper divisors (1968520600).

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

1321520000 is an frugal number, since it uses more digits than its factorization.

1321520000 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 16553 (or 16526 counting only the distinct ones).

The product of its (nonzero) digits is 60, while the sum is 14.

The square root of 1321520000 is about 36352.7165422338. The cubic root of 1321520000 is about 1097.3822048290.

Adding to 1321520000 its reverse (251231), we get a palindrome (1321771231).

The spelling of 1321520000 in words is "one billion, three hundred twenty-one million, five hundred twenty thousand".