661335330 has 128 divisors (see below), whose sum is σ = 1721212416. Its totient is φ = 162201600.

The previous prime is 661335287. The next prime is 661335361. The reversal of 661335330 is 33533166.

661335330 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 an unprimeable number.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 2744010 + ... + 2744250.

It is an arithmetic number, because the mean of its divisors is an integer number (13446972).

Almost surely, 2^661335330 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 661335330, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (860606208).

661335330 is an abundant number, since it is smaller than the sum of its proper divisors (1059877086).

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

661335330 is a wasteful number, since it uses less digits than its factorization.

661335330 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 412.

The product of its (nonzero) digits is 14580, while the sum is 30.

The square root of 661335330 is about 25716.4408501643. The cubic root of 661335330 is about 871.2455537512.

Adding to 661335330 its reverse (33533166), we get a palindrome (694868496).

The spelling of 661335330 in words is "six hundred sixty-one million, three hundred thirty-five thousand, three hundred thirty".