1644634 has 4 divisors (see below), whose sum is σ = 2466954. Its totient is φ = 822316.

The previous prime is 1644623. The next prime is 1644637. The reversal of 1644634 is 4364461.

It is a happy number.

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

It can be written as a sum of positive squares in only one way, i.e., 1288225 + 356409 = 1135^2 + 597^2 .

It is not an unprimeable number, because it can be changed into a prime (1644637) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 411157 + ... + 411160.

2^1644634 is an apocalyptic number.

1644634 is a deficient number, since it is larger than the sum of its proper divisors (822320).

1644634 is an equidigital number, since it uses as much as digits as its factorization.

1644634 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 822319.

The product of its digits is 6912, while the sum is 28.

The square root of 1644634 is about 1282.4328442457. The cubic root of 1644634 is about 118.0383385909.

It can be divided in two parts, 1644 and 634, that added together give a triangular number (2278 = T₆₇).

The spelling of 1644634 in words is "one million, six hundred forty-four thousand, six hundred thirty-four".