1556161 has 4 divisors (see below), whose sum is σ = 1565872. Its totient is φ = 1546452.

The previous prime is 1556147. The next prime is 1556173. The reversal of 1556161 is 1616551.

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 a cyclic number.

It is not a de Polignac number, because 1556161 - 2¹⁵ = 1523393 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1556561) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 4611 + ... + 4936.

It is an arithmetic number, because the mean of its divisors is an integer number (391468).

2^1556161 is an apocalyptic number.

It is an amenable number.

1556161 is a deficient number, since it is larger than the sum of its proper divisors (9711).

1556161 is an equidigital number, since it uses as much as digits as its factorization.

1556161 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9710.

The product of its digits is 900, while the sum is 25.

The square root of 1556161 is about 1247.4618230631. The cubic root of 1556161 is about 115.8825853156.

The spelling of 1556161 in words is "one million, five hundred fifty-six thousand, one hundred sixty-one".