661204611 has 48 divisors (see below), whose sum is σ = 1035141120. Its totient is φ = 405720000.

The previous prime is 661204571. The next prime is 661204633. The reversal of 661204611 is 116402166.

661204611 is a `hidden beast` number, since 6 + 612 + 0 + 46 + 1 + 1 = 666.

661204611 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 661204611 - 2⁶ = 661204547 is a prime.

It is a super-2 number, since 2×661204611² = 874383075215322642, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (661204651) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 573886 + ... + 575036.

It is an arithmetic number, because the mean of its divisors is an integer number (21565440).

Almost surely, 2^661204611 is an apocalyptic number.

661204611 is a deficient number, since it is larger than the sum of its proper divisors (373936509).

661204611 is a wasteful number, since it uses less digits than its factorization.

661204611 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1288 (or 1285 counting only the distinct ones).

The product of its (nonzero) digits is 1728, while the sum is 27.

The square root of 661204611 is about 25713.8991792377. The cubic root of 661204611 is about 871.1881467410.

Adding to 661204611 its reverse (116402166), we get a palindrome (777606777).

The spelling of 661204611 in words is "six hundred sixty-one million, two hundred four thousand, six hundred eleven".