721670400 has 648 divisors, whose sum is σ = 3024743904. Its totient is φ = 162201600.

The previous prime is 721670399. The next prime is 721670401. The reversal of 721670400 is 4076127.

It is an interprime number because it is at equal distance from previous prime (721670399) and next prime (721670401).

It is not an unprimeable number, because it can be changed into a prime (721670401) by changing a digit.

It is a polite number, since it can be written in 71 ways as a sum of consecutive naturals, for example, 10771167 + ... + 10771233.

Almost surely, 2^721670400 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 721670400, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1512371952).

721670400 is an abundant number, since it is smaller than the sum of its proper divisors (2303073504).

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

721670400 is a wasteful number, since it uses less digits than its factorization.

721670400 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 127 (or 105 counting only the distinct ones).

The product of its (nonzero) digits is 2352, while the sum is 27.

The square root of 721670400 is about 26863.9237640372. The cubic root of 721670400 is about 896.9735379195.

The spelling of 721670400 in words is "seven hundred twenty-one million, six hundred seventy thousand, four hundred".