1555009 has 9 divisors (see below), whose sum is σ = 1648803. Its totient is φ = 1466472.

The previous prime is 1554989. The next prime is 1555013. The reversal of 1555009 is 9005551.

The square root of 1555009 is 1247.

It is a perfect power (a square), and thus also a powerful number.

It can be written as a sum of positive squares in only one way, i.e., 815409 + 739600 = 903^2 + 860^2 .

It is not a de Polignac number, because 1555009 - 2⁵ = 1554977 is a prime.

It is a Duffinian number.

1555009 is a lucky number.

It is not an unprimeable number, because it can be changed into a prime (1555039) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 8 ways as a sum of consecutive naturals, for example, 36142 + ... + 36184.

2^1555009 is an apocalyptic number.

1555009 is the 1247-th square number.

1555009 is the 624-th centered octagonal number.

It is an amenable number.

1555009 is a deficient number, since it is larger than the sum of its proper divisors (93794).

1555009 is an frugal number, since it uses more digits than its factorization.

1555009 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 144 (or 72 counting only the distinct ones).

The product of its (nonzero) digits is 1125, while the sum is 25.

The cubic root of 1555009 is about 115.8539829422.

Multiplying 1555009 by its sum of digits (25), we get a square (38875225 = 6235²).

The spelling of 1555009 in words is "one million, five hundred fifty-five thousand, nine".