661033894452 has 12 divisors (see below), whose sum is σ = 1542412420416. Its totient is φ = 220344631480.

The previous prime is 661033894439. The next prime is 661033894459. The reversal of 661033894452 is 254498330166.

It is a tau number, because it is divible by the number of its divisors (12).

It is a super-2 number, since 2×661033894452² (a number of 24 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 661033894395 and 661033894404.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (661033894459) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 27543078924 + ... + 27543078947.

It is an arithmetic number, because the mean of its divisors is an integer number (128534368368).

Almost surely, 2^661033894452 is an apocalyptic number.

It is an amenable number.

661033894452 is an abundant number, since it is smaller than the sum of its proper divisors (881378525964).

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

661033894452 is a wasteful number, since it uses less digits than its factorization.

661033894452 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 55086157878 (or 55086157876 counting only the distinct ones).

The product of its (nonzero) digits is 3732480, while the sum is 51.

The spelling of 661033894452 in words is "six hundred sixty-one billion, thirty-three million, eight hundred ninety-four thousand, four hundred fifty-two".