1599661 has 4 divisors (see below), whose sum is σ = 1828192. Its totient is φ = 1371132.

The previous prime is 1599617. The next prime is 1599677. The reversal of 1599661 is 1669951.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is not a de Polignac number, because 1599661 - 2¹⁵ = 1566893 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 1599661.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1599601) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 114255 + ... + 114268.

It is an arithmetic number, because the mean of its divisors is an integer number (457048).

2^1599661 is an apocalyptic number.

It is an amenable number.

1599661 is a deficient number, since it is larger than the sum of its proper divisors (228531).

1599661 is an equidigital number, since it uses as much as digits as its factorization.

1599661 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 228530.

The product of its digits is 14580, while the sum is 37.

The square root of 1599661 is about 1264.7770554529. Note that the first 3 decimals coincide. The cubic root of 1599661 is about 116.9524485949.

Subtracting from 1599661 its product of digits (14580), we obtain a square (1585081 = 1259²).

The spelling of 1599661 in words is "one million, five hundred ninety-nine thousand, six hundred sixty-one".