1630505 has 4 divisors (see below), whose sum is σ = 1956612. Its totient is φ = 1304400.

The previous prime is 1630501. The next prime is 1630543. The reversal of 1630505 is 5050361.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 906304 + 724201 = 952^2 + 851^2 .

It is not a de Polignac number, because 1630505 - 2² = 1630501 is a prime.

It is an alternating number because its digits alternate between odd and even.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1630501) 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, 163046 + ... + 163055.

It is an arithmetic number, because the mean of its divisors is an integer number (489153).

2^1630505 is an apocalyptic number.

It is an amenable number.

1630505 is a deficient number, since it is larger than the sum of its proper divisors (326107).

1630505 is an equidigital number, since it uses as much as digits as its factorization.

1630505 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 326106.

The product of its (nonzero) digits is 450, while the sum is 20.

The square root of 1630505 is about 1276.9122914280. The cubic root of 1630505 is about 117.6993447248.

Adding to 1630505 its reverse (5050361), we get a palindrome (6680866).

The spelling of 1630505 in words is "one million, six hundred thirty thousand, five hundred five".