21887331811 has 2 divisors, whose sum is σ = 21887331812. Its totient is φ = 21887331810.

The previous prime is 21887331803. The next prime is 21887331847. The reversal of 21887331811 is 11813378812.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 21887331811 - 2³ = 21887331803 is a prime.

It is not a weakly prime, because it can be changed into another prime (21887301811) 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 as a sum of consecutive naturals, namely, 10943665905 + 10943665906.

It is an arithmetic number, because the mean of its divisors is an integer number (10943665906).

Almost surely, 2^21887331811 is an apocalyptic number.

21887331811 is a deficient number, since it is larger than the sum of its proper divisors (1).

21887331811 is an equidigital number, since it uses as much as digits as its factorization.

21887331811 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 64512, while the sum is 43.

The spelling of 21887331811 in words is "twenty-one billion, eight hundred eighty-seven million, three hundred thirty-one thousand, eight hundred eleven".