1606639 has 2 divisors, whose sum is σ = 1606640. Its totient is φ = 1606638.

The previous prime is 1606603. The next prime is 1606643. The reversal of 1606639 is 9366061.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 1606639 - 2¹³ = 1598447 is a prime.

It is a Chen prime.

It is a self number, because there is not a number n which added to its sum of digits gives 1606639.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1606669) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 803319 + 803320.

It is an arithmetic number, because the mean of its divisors is an integer number (803320).

2^1606639 is an apocalyptic number.

1606639 is a deficient number, since it is larger than the sum of its proper divisors (1).

1606639 is an equidigital number, since it uses as much as digits as its factorization.

1606639 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 5832, while the sum is 31.

The square root of 1606639 is about 1267.5326425777. The cubic root of 1606639 is about 117.1222575743.

The spelling of 1606639 in words is "one million, six hundred six thousand, six hundred thirty-nine".