661161066552 has 192 divisors, whose sum is σ = 2105376960960. Its totient is φ = 183503462400.

The previous prime is 661161066529. The next prime is 661161066557. The reversal of 661161066552 is 255660161166.

It is a junction number, because it is equal to n+sod(n) for n = 661161066498 and 661161066507.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (661161066557) 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, 4746052 + ... + 4883372.

It is an arithmetic number, because the mean of its divisors is an integer number (10965505005).

Almost surely, 2^661161066552 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 661161066552, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1052688480480).

661161066552 is an abundant number, since it is smaller than the sum of its proper divisors (1444215894408).

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

661161066552 is a wasteful number, since it uses less digits than its factorization.

661161066552 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 137614 (or 137607 counting only the distinct ones).

The product of its (nonzero) digits is 388800, while the sum is 45.

The spelling of 661161066552 in words is "six hundred sixty-one billion, one hundred sixty-one million, sixty-six thousand, five hundred fifty-two".