1643613 has 4 divisors (see below), whose sum is σ = 2191488. Its totient is φ = 1095740.

The previous prime is 1643599. The next prime is 1643617. The reversal of 1643613 is 3163461.

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.

It is a cyclic number.

It is not a de Polignac number, because 1643613 - 2⁴ = 1643597 is a prime.

It is a D-number.

1643613 is a lucky number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1643617) 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, 273933 + ... + 273938.

It is an arithmetic number, because the mean of its divisors is an integer number (547872).

2^1643613 is an apocalyptic number.

It is an amenable number.

1643613 is a deficient number, since it is larger than the sum of its proper divisors (547875).

1643613 is an equidigital number, since it uses as much as digits as its factorization.

1643613 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 547874.

The product of its digits is 1296, while the sum is 24.

The square root of 1643613 is about 1282.0347109185. The cubic root of 1643613 is about 118.0139071993.

The spelling of 1643613 in words is "one million, six hundred forty-three thousand, six hundred thirteen".