1639081 has 2 divisors, whose sum is σ = 1639082. Its totient is φ = 1639080.

The previous prime is 1639067. The next prime is 1639087. The reversal of 1639081 is 1809361.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1625625 + 13456 = 1275^2 + 116^2 .

It is a cyclic number.

It is not a de Polignac number, because 1639081 - 2⁹ = 1638569 is a prime.

It is a super-2 number, since 2×1639081² = 5373173049122, which contains 22 as substring.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (1639087) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 819540 + 819541.

It is an arithmetic number, because the mean of its divisors is an integer number (819541).

2^1639081 is an apocalyptic number.

It is an amenable number.

1639081 is a deficient number, since it is larger than the sum of its proper divisors (1).

1639081 is an equidigital number, since it uses as much as digits as its factorization.

1639081 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1296, while the sum is 28.

The square root of 1639081 is about 1280.2659879884. The cubic root of 1639081 is about 117.9053391930.

It can be divided in two parts, 16390 and 81, that added together give a triangular number (16471 = T₁₈₁).

The spelling of 1639081 in words is "one million, six hundred thirty-nine thousand, eighty-one".