21887827591 has 12 divisors (see below), whose sum is σ = 25468664760. Its totient is φ = 18755605680.

The previous prime is 21887827589. The next prime is 21887827597. The reversal of 21887827591 is 19572878812.

It is not a de Polignac number, because 21887827591 - 2¹ = 21887827589 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21887827597) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 113100 + ... + 237838.

It is an arithmetic number, because the mean of its divisors is an integer number (2122388730).

Almost surely, 2^21887827591 is an apocalyptic number.

21887827591 is a deficient number, since it is larger than the sum of its proper divisors (3580837169).

21887827591 is a wasteful number, since it uses less digits than its factorization.

21887827591 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 128334 (or 128327 counting only the distinct ones).

The product of its digits is 4515840, while the sum is 58.

The spelling of 21887827591 in words is "twenty-one billion, eight hundred eighty-seven million, eight hundred twenty-seven thousand, five hundred ninety-one".