721245600 has 144 divisors (see below), whose sum is σ = 2608583040. Its totient is φ = 192326400.

The previous prime is 721245599. The next prime is 721245601. The reversal of 721245600 is 6542127.

721245600 is a `hidden beast` number, since 7 + 2 + 12 + 45 + 600 = 666.

It is an interprime number because it is at equal distance from previous prime (721245599) and next prime (721245601).

It is a tau number, because it is divible by the number of its divisors (144).

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a zygodrome in base 4.

It is not an unprimeable number, because it can be changed into a prime (721245601) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 4905 + ... + 38295.

It is an arithmetic number, because the mean of its divisors is an integer number (18115160).

Almost surely, 2^721245600 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 721245600, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1304291520).

721245600 is an abundant number, since it is smaller than the sum of its proper divisors (1887337440).

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

721245600 is a wasteful number, since it uses less digits than its factorization.

721245600 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 33420 (or 33401 counting only the distinct ones).

The product of its (nonzero) digits is 3360, while the sum is 27.

The square root of 721245600 is about 26856.0160857861. The cubic root of 721245600 is about 896.7975068918.

Adding to 721245600 its reverse (6542127), we get a palindrome (727787727).

The spelling of 721245600 in words is "seven hundred twenty-one million, two hundred forty-five thousand, six hundred".