1561599 has 20 divisors (see below), whose sum is σ = 2513896. Its totient is φ = 960336.

The previous prime is 1561597. The next prime is 1561601. The reversal of 1561599 is 9951651.

1561599 is a `hidden beast` number, since 1 + 5 + 61 + 599 = 666.

It is an interprime number because it is at equal distance from previous prime (1561597) and next prime (1561601).

It is not a de Polignac number, because 1561599 - 2¹ = 1561597 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1561597) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 19 ways as a sum of consecutive naturals, for example, 312 + ... + 1794.

2^1561599 is an apocalyptic number.

1561599 is a deficient number, since it is larger than the sum of its proper divisors (952297).

1561599 is a wasteful number, since it uses less digits than its factorization.

1561599 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1508 (or 1499 counting only the distinct ones).

The product of its digits is 12150, while the sum is 36.

The square root of 1561599 is about 1249.6395480298. The cubic root of 1561599 is about 116.0174121702.

The spelling of 1561599 in words is "one million, five hundred sixty-one thousand, five hundred ninety-nine".