66099321 has 40 divisors (see below), whose sum is σ = 102322440. Its totient is φ = 42501888.

The previous prime is 66099317. The next prime is 66099331. The reversal of 66099321 is 12399066.

It can be written as a sum of positive squares in 4 ways, for example, as 19927296 + 46172025 = 4464^2 + 6795^2 .

It is not a de Polignac number, because 66099321 - 2² = 66099317 is a prime.

It is a super-2 number, since 2×66099321² = 8738240473322082, which contains 22 as substring.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66099301) by changing a digit.

It is a polite number, since it can be written in 39 ways as a sum of consecutive naturals, for example, 381991 + ... + 382163.

It is an arithmetic number, because the mean of its divisors is an integer number (2558061).

Almost surely, 2^66099321 is an apocalyptic number.

It is an amenable number.

66099321 is a deficient number, since it is larger than the sum of its proper divisors (36223119).

66099321 is a wasteful number, since it uses less digits than its factorization.

66099321 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 327 (or 318 counting only the distinct ones).

The product of its (nonzero) digits is 17496, while the sum is 36.

The square root of 66099321 is about 8130.1488916255. The cubic root of 66099321 is about 404.3266176317.

The spelling of 66099321 in words is "sixty-six million, ninety-nine thousand, three hundred twenty-one".