1645629 has 4 divisors (see below), whose sum is σ = 2194176. Its totient is φ = 1097084.

The previous prime is 1645613. The next prime is 1645643. The reversal of 1645629 is 9265461.

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 an emirpimes, since its reverse is a distinct semiprime: 9265461 = 3 ⋅3088487.

It is a cyclic number.

It is not a de Polignac number, because 1645629 - 2⁴ = 1645613 is a prime.

It is a D-number.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 1645629.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1645669) 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 3 ways as a sum of consecutive naturals, for example, 274269 + ... + 274274.

It is an arithmetic number, because the mean of its divisors is an integer number (548544).

2^1645629 is an apocalyptic number.

It is an amenable number.

1645629 is a deficient number, since it is larger than the sum of its proper divisors (548547).

1645629 is an equidigital number, since it uses as much as digits as its factorization.

1645629 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 548546.

The product of its digits is 12960, while the sum is 33.

The square root of 1645629 is about 1282.8207201320. The cubic root of 1645629 is about 118.0621381048.

The spelling of 1645629 in words is "one million, six hundred forty-five thousand, six hundred twenty-nine".