561371623 has 4 divisors (see below), whose sum is σ = 565792000. Its totient is φ = 556951248.

The previous prime is 561371617. The next prime is 561371633. The reversal of 561371623 is 326173165.

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 561371623 - 2¹⁷ = 561240551 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 (561371633) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2209998 + ... + 2210251.

It is an arithmetic number, because the mean of its divisors is an integer number (141448000).

Almost surely, 2^561371623 is an apocalyptic number.

561371623 is a deficient number, since it is larger than the sum of its proper divisors (4420377).

561371623 is a wasteful number, since it uses less digits than its factorization.

561371623 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4420376.

The product of its digits is 22680, while the sum is 34.

The square root of 561371623 is about 23693.2822335784. The cubic root of 561371623 is about 824.9294695750.

The spelling of 561371623 in words is "five hundred sixty-one million, three hundred seventy-one thousand, six hundred twenty-three".