661011008 has 56 divisors (see below), whose sum is σ = 1531022592. Its totient is φ = 277254144.

The previous prime is 661010971. The next prime is 661011023. The reversal of 661011008 is 800110166.

It is a happy number.

It is a tau number, because it is divible by the number of its divisors (56).

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 5360 + ... + 36752.

Almost surely, 2^661011008 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 661011008, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (765511296).

661011008 is an abundant number, since it is smaller than the sum of its proper divisors (870011584).

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

661011008 is a wasteful number, since it uses less digits than its factorization.

661011008 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 31459 (or 31449 counting only the distinct ones).

The product of its (nonzero) digits is 288, while the sum is 23.

The square root of 661011008 is about 25710.1343442620. The cubic root of 661011008 is about 871.1031094719.

The spelling of 661011008 in words is "six hundred sixty-one million, eleven thousand, eight".