3781961 has 2 divisors, whose sum is σ = 3781962. Its totient is φ = 3781960.

The previous prime is 3781951. The next prime is 3781993. The reversal of 3781961 is 1691873.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 3367225 + 414736 = 1835^2 + 644^2 .

It is a cyclic number.

It is not a de Polignac number, because 3781961 - 2¹⁰ = 3780937 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (3781901) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1890980 + 1890981.

It is an arithmetic number, because the mean of its divisors is an integer number (1890981).

Almost surely, 2^3781961 is an apocalyptic number.

3781961 is the 1040-th centered heptagonal number.

It is an amenable number.

3781961 is a deficient number, since it is larger than the sum of its proper divisors (1).

3781961 is an equidigital number, since it uses as much as digits as its factorization.

3781961 is an evil number, because the sum of its binary digits is even.

The product of its digits is 9072, while the sum is 35.

The square root of 3781961 is about 1944.7264589140. The cubic root of 3781961 is about 155.8017561788.

The spelling of 3781961 in words is "three million, seven hundred eighty-one thousand, nine hundred sixty-one".