1656289 has 4 divisors (see below), whose sum is σ = 1658880. Its totient is φ = 1653700.

The previous prime is 1656283. The next prime is 1656301. The reversal of 1656289 is 9826561.

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, and also a brilliant number, because the two primes have the same length.

It is a cyclic number.

It is not a de Polignac number, because 1656289 - 2⁵ = 1656257 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1656283) 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, 432 + ... + 1870.

It is an arithmetic number, because the mean of its divisors is an integer number (414720).

2^1656289 is an apocalyptic number.

It is an amenable number.

1656289 is a deficient number, since it is larger than the sum of its proper divisors (2591).

1656289 is a wasteful number, since it uses less digits than its factorization.

1656289 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2590.

The product of its digits is 25920, while the sum is 37.

The square root of 1656289 is about 1286.9689195936. The cubic root of 1656289 is about 118.3165159375.

Adding to 1656289 its product of digits (25920), we get a square (1682209 = 1297²).

The spelling of 1656289 in words is "one million, six hundred fifty-six thousand, two hundred eighty-nine".