166721366 has 8 divisors (see below), whose sum is σ = 285808080. Its totient is φ = 71452008.

The previous prime is 166721339. The next prime is 166721459. The reversal of 166721366 is 663127661.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 5954321 + ... + 5954348.

It is an arithmetic number, because the mean of its divisors is an integer number (35726010).

Almost surely, 2^166721366 is an apocalyptic number.

166721366 is a deficient number, since it is larger than the sum of its proper divisors (119086714).

166721366 is a wasteful number, since it uses less digits than its factorization.

166721366 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 11908678.

The product of its digits is 54432, while the sum is 38.

The square root of 166721366 is about 12912.0628096366. The cubic root of 166721366 is about 550.3814059704.

The spelling of 166721366 in words is "one hundred sixty-six million, seven hundred twenty-one thousand, three hundred sixty-six".