1623649 has 4 divisors (see below), whose sum is σ = 1628100. Its totient is φ = 1619200.

The previous prime is 1623647. The next prime is 1623667. The reversal of 1623649 is 9463261.

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 1140624 + 483025 = 1068^2 + 695^2 .

It is a cyclic number.

It is not a de Polignac number, because 1623649 - 2¹ = 1623647 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 1623649.

It is not an unprimeable number, because it can be changed into a prime (1623647) 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, 1624 + ... + 2425.

It is an arithmetic number, because the mean of its divisors is an integer number (407025).

2^1623649 is an apocalyptic number.

It is an amenable number.

1623649 is a deficient number, since it is larger than the sum of its proper divisors (4451).

1623649 is an equidigital number, since it uses as much as digits as its factorization.

1623649 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4450.

The product of its digits is 7776, while the sum is 31.

The square root of 1623649 is about 1274.2248624164. The cubic root of 1623649 is about 117.5341442947.

The spelling of 1623649 in words is "one million, six hundred twenty-three thousand, six hundred forty-nine".