21469945987 has 6 divisors (see below), whose sum is σ = 24975243348. Its totient is φ = 18402810804.

The previous prime is 21469945969. The next prime is 21469946027. The reversal of 21469945987 is 78954996412.

It is not a de Polignac number, because 21469945987 - 2³¹ = 19322462339 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21469945687) 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 5 ways as a sum of consecutive naturals, for example, 219081033 + ... + 219081130.

It is an arithmetic number, because the mean of its divisors is an integer number (4162540558).

Almost surely, 2^21469945987 is an apocalyptic number.

21469945987 is a deficient number, since it is larger than the sum of its proper divisors (3505297361).

21469945987 is an equidigital number, since it uses as much as digits as its factorization.

21469945987 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 438162177 (or 438162170 counting only the distinct ones).

The product of its digits is 39191040, while the sum is 64.

The spelling of 21469945987 in words is "twenty-one billion, four hundred sixty-nine million, nine hundred forty-five thousand, nine hundred eighty-seven".