2251605 has 8 divisors (see below), whose sum is σ = 3602592. Its totient is φ = 1200848.

The previous prime is 2251603. The next prime is 2251637. The reversal of 2251605 is 5061522.

2251605 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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

It is a cyclic number.

It is not a de Polignac number, because 2251605 - 2¹ = 2251603 is a prime.

2251605 is a lucky number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2251603) 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, 75039 + ... + 75068.

It is an arithmetic number, because the mean of its divisors is an integer number (450324).

2^2251605 is an apocalyptic number.

It is an amenable number.

2251605 is a deficient number, since it is larger than the sum of its proper divisors (1350987).

2251605 is a wasteful number, since it uses less digits than its factorization.

2251605 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 150115.

The product of its (nonzero) digits is 600, while the sum is 21.

The square root of 2251605 is about 1500.5349046257. The cubic root of 2251605 is about 131.0682200080.

It can be divided in two parts, 225 and 1605, that added together give a triangular number (1830 = T₆₀).

The spelling of 2251605 in words is "two million, two hundred fifty-one thousand, six hundred five".