1606544749 has 4 divisors (see below), whose sum is σ = 1623107164. Its totient is φ = 1589982336.

The previous prime is 1606544747. The next prime is 1606544767. The reversal of 1606544749 is 9474456061.

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 1153621225 + 452923524 = 33965^2 + 21282^2 .

It is a cyclic number.

It is not a de Polignac number, because 1606544749 - 2¹ = 1606544747 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 1606544699 and 1606544708.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1606544743) 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, 8281062 + ... + 8281255.

It is an arithmetic number, because the mean of its divisors is an integer number (405776791).

Almost surely, 2^1606544749 is an apocalyptic number.

It is an amenable number.

1606544749 is a deficient number, since it is larger than the sum of its proper divisors (16562415).

1606544749 is an equidigital number, since it uses as much as digits as its factorization.

1606544749 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 16562414.

The product of its (nonzero) digits is 725760, while the sum is 46.

The square root of 1606544749 is about 40081.7258735200. The cubic root of 1606544749 is about 1171.1996726400.

The spelling of 1606544749 in words is "one billion, six hundred six million, five hundred forty-four thousand, seven hundred forty-nine".