21887331847 has 2 divisors, whose sum is σ = 21887331848. Its totient is φ = 21887331846.

The previous prime is 21887331811. The next prime is 21887331877. The reversal of 21887331847 is 74813378812.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 21887331847 - 2²³ = 21878943239 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 21887331794 and 21887331803.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21887331877) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10943665923 + 10943665924.

It is an arithmetic number, because the mean of its divisors is an integer number (10943665924).

Almost surely, 2^21887331847 is an apocalyptic number.

21887331847 is a deficient number, since it is larger than the sum of its proper divisors (1).

21887331847 is an equidigital number, since it uses as much as digits as its factorization.

21887331847 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 1806336, while the sum is 52.

The spelling of 21887331847 in words is "twenty-one billion, eight hundred eighty-seven million, three hundred thirty-one thousand, eight hundred forty-seven".