660198400 has 264 divisors, whose sum is σ = 1822992696. Its totient is φ = 235929600.

The previous prime is 660198391. The next prime is 660198421. The reversal of 660198400 is 4891066.

It can be written as a sum of positive squares in 12 ways, for example, as 120472576 + 539725824 = 10976^2 + 23232^2 .

It is a Harshad number since it is a multiple of its sum of digits (34).

It is a congruent number.

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, 16102380 + ... + 16102420.

Almost surely, 2^660198400 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 660198400, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (911496348).

660198400 is an abundant number, since it is smaller than the sum of its proper divisors (1162794296).

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

660198400 is a wasteful number, since it uses less digits than its factorization.

660198400 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 125 (or 102 counting only the distinct ones).

The product of its (nonzero) digits is 10368, while the sum is 34.

The square root of 660198400 is about 25694.3262219502. The cubic root of 660198400 is about 870.7460021446.

The spelling of 660198400 in words is "six hundred sixty million, one hundred ninety-eight thousand, four hundred".