661336700 has 54 divisors (see below), whose sum is σ = 1450985256. Its totient is φ = 261629280.

The previous prime is 661336693. The next prime is 661336717. The reversal of 661336700 is 7633166.

It is a happy number.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 17 ways as a sum of consecutive naturals, for example, 3323201 + ... + 3323399.

Almost surely, 2^661336700 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 661336700, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (725492628).

661336700 is an abundant number, since it is smaller than the sum of its proper divisors (789648556).

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

661336700 is a wasteful number, since it uses less digits than its factorization.

661336700 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 579 (or 373 counting only the distinct ones).

The product of its (nonzero) digits is 13608, while the sum is 32.

The square root of 661336700 is about 25716.4674868070. The cubic root of 661336700 is about 871.2461553651.

Adding to 661336700 its reverse (7633166), we get a palindrome (668969866).

The spelling of 661336700 in words is "six hundred sixty-one million, three hundred thirty-six thousand, seven hundred".