21963487889 has 8 divisors (see below), whose sum is σ = 25103379840. Its totient is φ = 18824158656.

The previous prime is 21963487813. The next prime is 21963487981. The reversal of 21963487889 is 98878436912.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 21963487889 - 2²⁰ = 21962439313 is a prime.

It is not an unprimeable number, because it can be changed into a prime (21963457889) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 53429 + ... + 216290.

It is an arithmetic number, because the mean of its divisors is an integer number (3137922480).

Almost surely, 2^21963487889 is an apocalyptic number.

It is an amenable number.

21963487889 is a deficient number, since it is larger than the sum of its proper divisors (3139891951).

21963487889 is a wasteful number, since it uses less digits than its factorization.

21963487889 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 281359.

The product of its digits is 41803776, while the sum is 65.

The spelling of 21963487889 in words is "twenty-one billion, nine hundred sixty-three million, four hundred eighty-seven thousand, eight hundred eighty-nine".