4090861 has 2 divisors, whose sum is σ = 4090862. Its totient is φ = 4090860.

The previous prime is 4090859. The next prime is 4090901. The reversal of 4090861 is 1680904.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 2540836 + 1550025 = 1594^2 + 1245^2 .

It is a cyclic number.

It is not a de Polignac number, because 4090861 - 2¹ = 4090859 is a prime.

Together with 4090859, it forms a pair of twin primes.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (4090841) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 2045430 + 2045431.

It is an arithmetic number, because the mean of its divisors is an integer number (2045431).

Almost surely, 2^4090861 is an apocalyptic number.

It is an amenable number.

4090861 is a deficient number, since it is larger than the sum of its proper divisors (1).

4090861 is an equidigital number, since it uses as much as digits as its factorization.

4090861 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1728, while the sum is 28.

The square root of 4090861 is about 2022.5876989639. The cubic root of 4090861 is about 159.9330579337.

The spelling of 4090861 in words is "four million, ninety thousand, eight hundred sixty-one".