921243400 has 192 divisors, whose sum is σ = 2694113280. Its totient is φ = 284601600.

The previous prime is 921243373. The next prime is 921243419. The reversal of 921243400 is 4342129.

It is a Harshad number since it is a multiple of its sum of digits (25).

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 2510017 + ... + 2510383.

It is an arithmetic number, because the mean of its divisors is an integer number (14031840).

Almost surely, 2^921243400 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 921243400, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1347056640).

921243400 is an abundant number, since it is smaller than the sum of its proper divisors (1772869880).

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

921243400 is a wasteful number, since it uses less digits than its factorization.

921243400 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 564 (or 555 counting only the distinct ones).

The product of its (nonzero) digits is 1728, while the sum is 25.

The square root of 921243400 is about 30351.9916974158. The cubic root of 921243400 is about 973.0267872874.

Adding to 921243400 its reverse (4342129), we get a palindrome (925585529).

The spelling of 921243400 in words is "nine hundred twenty-one million, two hundred forty-three thousand, four hundred".