166322981 has 8 divisors (see below), whose sum is σ = 183929664. Its totient is φ = 149130720.

The previous prime is 166322977. The next prime is 166322983. The reversal of 166322981 is 189223661.

It is a happy number.

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

It is a cyclic number.

It is not a de Polignac number, because 166322981 - 2² = 166322977 is a prime.

It is a super-2 number, since 2×166322981² = 55326668017452722, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (166322983) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 102761 + ... + 104366.

It is an arithmetic number, because the mean of its divisors is an integer number (22991208).

Almost surely, 2^166322981 is an apocalyptic number.

166322981 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

166322981 is a deficient number, since it is larger than the sum of its proper divisors (17606683).

166322981 is a wasteful number, since it uses less digits than its factorization.

166322981 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 207211.

The product of its digits is 31104, while the sum is 38.

The square root of 166322981 is about 12896.6267294979. The cubic root of 166322981 is about 549.9426728128.

The spelling of 166322981 in words is "one hundred sixty-six million, three hundred twenty-two thousand, nine hundred eighty-one".