4039561 has 2 divisors, whose sum is σ = 4039562. Its totient is φ = 4039560.

The previous prime is 4039547. The next prime is 4039583. The reversal of 4039561 is 1659304.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 3980025 + 59536 = 1995^2 + 244^2 .

It is a cyclic number.

It is not a de Polignac number, because 4039561 - 2⁷ = 4039433 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (4039661) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 2019780 + 2019781.

It is an arithmetic number, because the mean of its divisors is an integer number (2019781).

Almost surely, 2^4039561 is an apocalyptic number.

It is an amenable number.

4039561 is a deficient number, since it is larger than the sum of its proper divisors (1).

4039561 is an equidigital number, since it uses as much as digits as its factorization.

4039561 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 3240, while the sum is 28.

The square root of 4039561 is about 2009.8659159257. The cubic root of 4039561 is about 159.2617157798.

It can be divided in two parts, 40 and 39561, that added together give a square (39601 = 199²).

The spelling of 4039561 in words is "four million, thirty-nine thousand, five hundred sixty-one".