4045681 has 2 divisors, whose sum is σ = 4045682. Its totient is φ = 4045680.

The previous prime is 4045663. The next prime is 4045687. The reversal of 4045681 is 1865404.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 3027600 + 1018081 = 1740^2 + 1009^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-4045681 is a prime.

It is a super-2 number, since 2×4045681² = 32735069507522, which contains 22 as substring.

It is a Chen prime.

4045681 is a lucky number.

It is not a weakly prime, because it can be changed into another prime (4045687) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 2022840 + 2022841.

It is an arithmetic number, because the mean of its divisors is an integer number (2022841).

Almost surely, 2^4045681 is an apocalyptic number.

It is an amenable number.

4045681 is a deficient number, since it is larger than the sum of its proper divisors (1).

4045681 is an equidigital number, since it uses as much as digits as its factorization.

4045681 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 3840, while the sum is 28.

The square root of 4045681 is about 2011.3878293358. The cubic root of 4045681 is about 159.3421032192.

The spelling of 4045681 in words is "four million, forty-five thousand, six hundred eighty-one".