1321573478400 has 468 divisors, whose sum is σ = 5409845814672. Its totient is φ = 302072463360.

The previous prime is 1321573478383. The next prime is 1321573478411. The reversal of 1321573478400 is 48743751231.

1321573478400 is a `hidden beast` number, since 1 + 3 + 2 + 1 + 573 + 4 + 78 + 4 + 0 + 0 = 666.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a congruent number.

It is an unprimeable number.

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 35 ways as a sum of consecutive naturals, for example, 6348772 + ... + 6553628.

It is an arithmetic number, because the mean of its divisors is an integer number (11559499604).

Almost surely, 2^{1321573478400} is an apocalyptic number.

1321573478400 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 1321573478400, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2704922907336).

1321573478400 is an abundant number, since it is smaller than the sum of its proper divisors (4088272336272).

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

1321573478400 is a wasteful number, since it uses less digits than its factorization.

1321573478400 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 204904 (or 204874 counting only the distinct ones).

The product of its (nonzero) digits is 564480, while the sum is 45.

The spelling of 1321573478400 in words is "one trillion, three hundred twenty-one billion, five hundred seventy-three million, four hundred seventy-eight thousand, four hundred".