3661623 has 54 divisors (see below), whose sum is σ = 6775704. Its totient is φ = 1896048.

The previous prime is 3661601. The next prime is 3661633. The reversal of 3661623 is 3261663.

3661623 is a `hidden beast` number, since 36 + 6 + 1 + 623 = 666.

It is not a de Polignac number, because 3661623 - 2⁵ = 3661591 is a prime.

It is an Ulam number.

Its product of digits (3888) is a multiple of the sum of its prime factors (81).

3661623 is a lucky number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (3661633) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 53 ways as a sum of consecutive naturals, for example, 159190 + ... + 159212.

It is an arithmetic number, because the mean of its divisors is an integer number (125476).

Almost surely, 2^3661623 is an apocalyptic number.

3661623 is a deficient number, since it is larger than the sum of its proper divisors (3114081).

3661623 is a wasteful number, since it uses less digits than its factorization.

3661623 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 81 (or 52 counting only the distinct ones).

The product of its digits is 3888, while the sum is 27.

The square root of 3661623 is about 1913.5367778018. The cubic root of 3661623 is about 154.1314304991.

The spelling of 3661623 in words is "three million, six hundred sixty-one thousand, six hundred twenty-three".