66644533699580 has 24 divisors (see below), whose sum is σ = 147319495547280. Its totient is φ = 25254770664960.

The previous prime is 66644533699571. The next prime is 66644533699651. The reversal of 66644533699580 is 8599633544666.

It is a junction number, because it is equal to n+sod(n) for n = 66644533699498 and 66644533699507.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 87690175541 + ... + 87690176300.

It is an arithmetic number, because the mean of its divisors is an integer number (6138312314470).

Almost surely, 2^{66644533699580} is an apocalyptic number.

It is an amenable number.

66644533699580 is an abundant number, since it is smaller than the sum of its proper divisors (80674961847700).

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

66644533699580 is a wasteful number, since it uses less digits than its factorization.

66644533699580 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 175380351869 (or 175380351867 counting only the distinct ones).

The product of its (nonzero) digits is 3023308800, while the sum is 74.

The spelling of 66644533699580 in words is "sixty-six trillion, six hundred forty-four billion, five hundred thirty-three million, six hundred ninety-nine thousand, five hundred eighty".