3661421 has 2 divisors, whose sum is σ = 3661422. Its totient is φ = 3661420.

The previous prime is 3661417. The next prime is 3661429. The reversal of 3661421 is 1241663.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 2758921 + 902500 = 1661^2 + 950^2 .

It is a cyclic number.

It is not a de Polignac number, because 3661421 - 2² = 3661417 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (3661429) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1830710 + 1830711.

It is an arithmetic number, because the mean of its divisors is an integer number (1830711).

Almost surely, 2^3661421 is an apocalyptic number.

It is an amenable number.

3661421 is a deficient number, since it is larger than the sum of its proper divisors (1).

3661421 is an equidigital number, since it uses as much as digits as its factorization.

3661421 is an evil number, because the sum of its binary digits is even.

The product of its digits is 864, while the sum is 23.

The square root of 3661421 is about 1913.4839952296. The cubic root of 3661421 is about 154.1285961347.

The spelling of 3661421 in words is "three million, six hundred sixty-one thousand, four hundred twenty-one".