166240321 has 16 divisors (see below), whose sum is σ = 186213888. Its totient is φ = 147369600.

The previous prime is 166240313. The next prime is 166240337. The reversal of 166240321 is 123042661.

It is a cyclic number.

It is not a de Polignac number, because 166240321 - 2³ = 166240313 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (166240301) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 53706 + ... + 56716.

It is an arithmetic number, because the mean of its divisors is an integer number (11638368).

Almost surely, 2^166240321 is an apocalyptic number.

It is an amenable number.

166240321 is a deficient number, since it is larger than the sum of its proper divisors (19973567).

166240321 is a wasteful number, since it uses less digits than its factorization.

166240321 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3192.

The product of its (nonzero) digits is 1728, while the sum is 25.

The square root of 166240321 is about 12893.4216172434. The cubic root of 166240321 is about 549.8515533258.

Adding to 166240321 its reverse (123042661), we get a palindrome (289282982).

The spelling of 166240321 in words is "one hundred sixty-six million, two hundred forty thousand, three hundred twenty-one".