21986085487 has 2 divisors, whose sum is σ = 21986085488. Its totient is φ = 21986085486.

The previous prime is 21986085463. The next prime is 21986085493. The reversal of 21986085487 is 78458068912.

It is a happy number.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 21986085487 - 2²³ = 21977696879 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21986085437) 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 as a sum of consecutive naturals, namely, 10993042743 + 10993042744.

It is an arithmetic number, because the mean of its divisors is an integer number (10993042744).

Almost surely, 2^21986085487 is an apocalyptic number.

21986085487 is a deficient number, since it is larger than the sum of its proper divisors (1).

21986085487 is an equidigital number, since it uses as much as digits as its factorization.

21986085487 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 7741440, while the sum is 58.

The spelling of 21986085487 in words is "twenty-one billion, nine hundred eighty-six million, eighty-five thousand, four hundred eighty-seven".