2661623 has 4 divisors (see below), whose sum is σ = 2687568. Its totient is φ = 2635680.

The previous prime is 2661611. The next prime is 2661641. The reversal of 2661623 is 3261662.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 2661623 - 2¹² = 2657527 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 2661592 and 2661601.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2661643) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 12818 + ... + 13023.

It is an arithmetic number, because the mean of its divisors is an integer number (671892).

2^2661623 is an apocalyptic number.

2661623 is a deficient number, since it is larger than the sum of its proper divisors (25945).

2661623 is a wasteful number, since it uses less digits than its factorization.

2661623 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 25944.

The product of its digits is 2592, while the sum is 26.

The square root of 2661623 is about 1631.4481297301. The cubic root of 2661623 is about 138.5847726143.

The spelling of 2661623 in words is "two million, six hundred sixty-one thousand, six hundred twenty-three".