661623330 has 32 divisors (see below), whose sum is σ = 1605744000. Its totient is φ = 174449792.

The previous prime is 661623329. The next prime is 661623337. The reversal of 661623330 is 33326166.

661623330 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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

It is not an unprimeable number, because it can be changed into a prime (661623337) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 121230 + ... + 126569.

It is an arithmetic number, because the mean of its divisors is an integer number (50179500).

Almost surely, 2^661623330 is an apocalyptic number.

661623330 is an abundant number, since it is smaller than the sum of its proper divisors (944120670).

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

661623330 is a wasteful number, since it uses less digits than its factorization.

661623330 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 247898.

The product of its (nonzero) digits is 11664, while the sum is 30.

The square root of 661623330 is about 25722.0397713712. The cubic root of 661623330 is about 871.3720061440.

Adding to 661623330 its reverse (33326166), we get a palindrome (694949496).

The spelling of 661623330 in words is "six hundred sixty-one million, six hundred twenty-three thousand, three hundred thirty".