661109822694 has 48 divisors (see below), whose sum is σ = 1508407442880. Its totient is φ = 208686630960.

The previous prime is 661109822669. The next prime is 661109822701. The reversal of 661109822694 is 496228901166.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 661109822694.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 451929 + ... + 1235499.

It is an arithmetic number, because the mean of its divisors is an integer number (31425155060).

Almost surely, 2^661109822694 is an apocalyptic number.

661109822694 is an abundant number, since it is smaller than the sum of its proper divisors (847297620186).

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

661109822694 is a wasteful number, since it uses less digits than its factorization.

661109822694 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 786065 (or 786062 counting only the distinct ones).

The product of its (nonzero) digits is 2239488, while the sum is 54.

The spelling of 661109822694 in words is "six hundred sixty-one billion, one hundred nine million, eight hundred twenty-two thousand, six hundred ninety-four".