661267200 has 432 divisors, whose sum is σ = 2481841152. Its totient is φ = 153600000.

The previous prime is 661267183. The next prime is 661267223. The reversal of 661267200 is 2762166.

It is a Harshad number since it is a multiple of its sum of digits (30).

It is an unprimeable number.

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 47 ways as a sum of consecutive naturals, for example, 6547150 + ... + 6547250.

Almost surely, 2^661267200 is an apocalyptic number.

661267200 is a gapful number since it is divisible by the number (60) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 661267200, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1240920576).

661267200 is an abundant number, since it is smaller than the sum of its proper divisors (1820573952).

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

661267200 is a wasteful number, since it uses less digits than its factorization.

661267200 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 172 (or 153 counting only the distinct ones).

The product of its (nonzero) digits is 6048, while the sum is 30.

The square root of 661267200 is about 25715.1161770660. The cubic root of 661267200 is about 871.2156344877.

The spelling of 661267200 in words is "six hundred sixty-one million, two hundred sixty-seven thousand, two hundred".