1613665 has 8 divisors (see below), whose sum is σ = 1963368. Its totient is φ = 1272960.

The previous prime is 1613653. The next prime is 1613669. The reversal of 1613665 is 5663161.

It can be written as a sum of positive squares in 4 ways, for example, as 421201 + 1192464 = 649^2 + 1092^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 1613665 - 2⁹ = 1613153 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1613669) 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 7 ways as a sum of consecutive naturals, for example, 1846 + ... + 2575.

It is an arithmetic number, because the mean of its divisors is an integer number (245421).

2^1613665 is an apocalyptic number.

It is an amenable number.

1613665 is a deficient number, since it is larger than the sum of its proper divisors (349703).

1613665 is an equidigital number, since it uses as much as digits as its factorization.

1613665 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4499.

The product of its digits is 3240, while the sum is 28.

The square root of 1613665 is about 1270.3011453982. The cubic root of 1613665 is about 117.2927385896.

It can be divided in two parts, 1613 and 665, that added together give a triangular number (2278 = T₆₇).

The spelling of 1613665 in words is "one million, six hundred thirteen thousand, six hundred sixty-five".