3977681 has 2 divisors, whose sum is σ = 3977682. Its totient is φ = 3977680.

The previous prime is 3977663. The next prime is 3977693. The reversal of 3977681 is 1867793.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 3094081 + 883600 = 1759^2 + 940^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-3977681 is a prime.

It is a super-2 number, since 2×3977681² = 31643892275522, which contains 22 as substring.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (3977621) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1988840 + 1988841.

It is an arithmetic number, because the mean of its divisors is an integer number (1988841).

Almost surely, 2^3977681 is an apocalyptic number.

It is an amenable number.

3977681 is a deficient number, since it is larger than the sum of its proper divisors (1).

3977681 is an equidigital number, since it uses as much as digits as its factorization.

3977681 is an evil number, because the sum of its binary digits is even.

The product of its digits is 63504, while the sum is 41.

The square root of 3977681 is about 1994.4124448067. The cubic root of 3977681 is about 158.4443109929. Note that the first 3 decimals are identical.

The spelling of 3977681 in words is "three million, nine hundred seventy-seven thousand, six hundred eighty-one".