21436589568 has 80 divisors (see below), whose sum is σ = 58501474416. Its totient is φ = 6971228160.

The previous prime is 21436589563. The next prime is 21436589599. The reversal of 21436589568 is 86598563412.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21436589563) 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, 107221 + ... + 233172.

Almost surely, 2^21436589568 is an apocalyptic number.

It is an amenable number.

21436589568 is an abundant number, since it is smaller than the sum of its proper divisors (37064884848).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21436589568 is an equidigital number, since it uses as much as digits as its factorization.

21436589568 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 340455 (or 340439 counting only the distinct ones).

The product of its digits is 12441600, while the sum is 57.

The spelling of 21436589568 in words is "twenty-one billion, four hundred thirty-six million, five hundred eighty-nine thousand, five hundred sixty-eight".