621066400 has 144 divisors (see below), whose sum is σ = 1589898240. Its totient is φ = 236620800.

The previous prime is 621066371. The next prime is 621066421. The reversal of 621066400 is 4660126.

It is a happy number.

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 23 ways as a sum of consecutive naturals, for example, 1959042 + ... + 1959358.

It is an arithmetic number, because the mean of its divisors is an integer number (11040960).

Almost surely, 2^621066400 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 621066400, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (794949120).

621066400 is an abundant number, since it is smaller than the sum of its proper divisors (968831840).

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

621066400 is a wasteful number, since it uses less digits than its factorization.

621066400 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 447 (or 434 counting only the distinct ones).

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

The square root of 621066400 is about 24921.2038232506. The cubic root of 621066400 is about 853.1905007248.

The spelling of 621066400 in words is "six hundred twenty-one million, sixty-six thousand, four hundred".