2405661 has 8 divisors (see below), whose sum is σ = 3220800. Its totient is φ = 1597152.

The previous prime is 2405651. The next prime is 2405677. The reversal of 2405661 is 1665042.

2405661 = 513² + 514² + ... + 521².

2405661 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 not a de Polignac number, because 2405661 - 2⁹ = 2405149 is a prime.

It is an Ulam number.

It is a plaindrome in base 14.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2405621) 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, 736 + ... + 2313.

It is an arithmetic number, because the mean of its divisors is an integer number (402600).

2^2405661 is an apocalyptic number.

It is an amenable number.

2405661 is a deficient number, since it is larger than the sum of its proper divisors (815139).

2405661 is a wasteful number, since it uses less digits than its factorization.

2405661 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3315.

The product of its (nonzero) digits is 1440, while the sum is 24.

The square root of 2405661 is about 1551.0193422392. The cubic root of 2405661 is about 133.9917756889.

The spelling of 2405661 in words is "two million, four hundred five thousand, six hundred sixty-one".