3166721 has 2 divisors, whose sum is σ = 3166722. Its totient is φ = 3166720.

The previous prime is 3166679. The next prime is 3166729. The reversal of 3166721 is 1276613.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 2283121 + 883600 = 1511^2 + 940^2 .

It is a cyclic number.

It is not a de Polignac number, because 3166721 - 2¹⁴ = 3150337 is a prime.

It is not a weakly prime, because it can be changed into another prime (3166729) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1583360 + 1583361.

It is an arithmetic number, because the mean of its divisors is an integer number (1583361).

Almost surely, 2^3166721 is an apocalyptic number.

It is an amenable number.

3166721 is a deficient number, since it is larger than the sum of its proper divisors (1).

3166721 is an equidigital number, since it uses as much as digits as its factorization.

3166721 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1512, while the sum is 26.

The square root of 3166721 is about 1779.5283082885. The cubic root of 3166721 is about 146.8486417767.

The spelling of 3166721 in words is "three million, one hundred sixty-six thousand, seven hundred twenty-one".