23005551591 has 24 divisors (see below), whose sum is σ = 36460743696. Its totient is φ = 13862154240.

The previous prime is 23005551589. The next prime is 23005551599. The reversal of 23005551591 is 19515550032.

23005551591 is a `hidden beast` number, since 2 + 3 + 0 + 0 + 55 + 515 + 91 = 666.

It is not a de Polignac number, because 23005551591 - 2¹ = 23005551589 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (23005551599) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 654490 + ... + 688743.

It is an arithmetic number, because the mean of its divisors is an integer number (1519197654).

Almost surely, 2^23005551591 is an apocalyptic number.

23005551591 is a deficient number, since it is larger than the sum of its proper divisors (13455192105).

23005551591 is a wasteful number, since it uses less digits than its factorization.

23005551591 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1343423 (or 1343420 counting only the distinct ones).

The product of its (nonzero) digits is 33750, while the sum is 36.

The spelling of 23005551591 in words is "twenty-three billion, five million, five hundred fifty-one thousand, five hundred ninety-one".