8721400 has 24 divisors (see below), whose sum is σ = 20277720. Its totient is φ = 3488480.

The previous prime is 8721379. The next prime is 8721403. The reversal of 8721400 is 41278.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (8721403) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 21604 + ... + 22003.

It is an arithmetic number, because the mean of its divisors is an integer number (844905).

Almost surely, 2^8721400 is an apocalyptic number.

It is an amenable number.

8721400 is an abundant number, since it is smaller than the sum of its proper divisors (11556320).

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

8721400 is a wasteful number, since it uses less digits than its factorization.

8721400 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 43623 (or 43614 counting only the distinct ones).

The product of its (nonzero) digits is 448, while the sum is 22.

The square root of 8721400 is about 2953.2016524443. The cubic root of 8721400 is about 205.8395080112.

Adding to 8721400 its reverse (41278), we get a palindrome (8762678).

The spelling of 8721400 in words is "eight million, seven hundred twenty-one thousand, four hundred".