661789920288 has 96 divisors (see below), whose sum is σ = 2033793498240. Its totient is φ = 184471050240.

The previous prime is 661789920283. The next prime is 661789920301. The reversal of 661789920288 is 882029987166.

It is a tau number, because it is divible by the number of its divisors (96).

It is not an unprimeable number, because it can be changed into a prime (661789920283) 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, 11982283 + ... + 12037386.

It is an arithmetic number, because the mean of its divisors is an integer number (21185348940).

Almost surely, 2^661789920288 is an apocalyptic number.

It is an amenable number.

661789920288 is an abundant number, since it is smaller than the sum of its proper divisors (1372003577952).

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

661789920288 is a wasteful number, since it uses less digits than its factorization.

661789920288 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 24019730 (or 24019722 counting only the distinct ones).

The product of its (nonzero) digits is 41803776, while the sum is 66.

The spelling of 661789920288 in words is "six hundred sixty-one billion, seven hundred eighty-nine million, nine hundred twenty thousand, two hundred eighty-eight".