1321900800 has 324 divisors, whose sum is σ = 4803624840. Its totient is φ = 319897600.

The previous prime is 1321900793. The next prime is 1321900817. The reversal of 1321900800 is 80091231.

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

It is an unprimeable number.

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 35 ways as a sum of consecutive naturals, for example, 2322916 + ... + 2323484.

Almost surely, 2^1321900800 is an apocalyptic number.

1321900800 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 1321900800, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2401812420).

1321900800 is an abundant number, since it is smaller than the sum of its proper divisors (3481724040).

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

1321900800 is a wasteful number, since it uses less digits than its factorization.

1321900800 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 620 (or 590 counting only the distinct ones).

The product of its (nonzero) digits is 432, while the sum is 24.

The square root of 1321900800 is about 36357.9537377999. The cubic root of 1321900800 is about 1097.4875993777.

It can be divided in two parts, 132 and 1900800, that multiplied together give a square (250905600 = 15840²).

The spelling of 1321900800 in words is "one billion, three hundred twenty-one million, nine hundred thousand, eight hundred".