661711610 has 32 divisors (see below), whose sum is σ = 1420422912. Its totient is φ = 217008000.

The previous prime is 661711597. The next prime is 661711657. The reversal of 661711610 is 16117166.

It is a Curzon number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 203891 + ... + 207110.

It is an arithmetic number, because the mean of its divisors is an integer number (44388216).

Almost surely, 2^661711610 is an apocalyptic number.

661711610 is an abundant number, since it is smaller than the sum of its proper divisors (758711302).

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

661711610 is a wasteful number, since it uses less digits than its factorization.

661711610 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 411038.

The product of its (nonzero) digits is 1512, while the sum is 29.

The square root of 661711610 is about 25723.7557522225. The cubic root of 661711610 is about 871.4107599666.

Adding to 661711610 its reverse (16117166), we get a palindrome (677828776).

The spelling of 661711610 in words is "six hundred sixty-one million, seven hundred eleven thousand, six hundred ten".