3661381 has 2 divisors, whose sum is σ = 3661382. Its totient is φ = 3661380.

The previous prime is 3661369. The next prime is 3661391. The reversal of 3661381 is 1831663.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 3348900 + 312481 = 1830^2 + 559^2 .

It is a cyclic number.

It is not a de Polignac number, because 3661381 - 2¹³ = 3653189 is a prime.

It is a super-2 number, since 2×3661381² = 26811421654322, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (3661391) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1830690 + 1830691.

It is an arithmetic number, because the mean of its divisors is an integer number (1830691).

Almost surely, 2^3661381 is an apocalyptic number.

It is an amenable number.

3661381 is a deficient number, since it is larger than the sum of its proper divisors (1).

3661381 is an equidigital number, since it uses as much as digits as its factorization.

3661381 is an evil number, because the sum of its binary digits is even.

The product of its digits is 2592, while the sum is 28.

The square root of 3661381 is about 1913.4735430625. The cubic root of 3661381 is about 154.1280348621.

The spelling of 3661381 in words is "three million, six hundred sixty-one thousand, three hundred eighty-one".