21699439512 has 16 divisors (see below), whose sum is σ = 54248598840. Its totient is φ = 7233146496.

The previous prime is 21699439499. The next prime is 21699439513. The reversal of 21699439512 is 21593499612.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21699439513) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 452071633 + ... + 452071680.

Almost surely, 2^21699439512 is an apocalyptic number.

It is an amenable number.

21699439512 is an abundant number, since it is smaller than the sum of its proper divisors (32549159328).

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

21699439512 is a wasteful number, since it uses less digits than its factorization.

21699439512 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 904143322 (or 904143318 counting only the distinct ones).

The product of its digits is 1049760, while the sum is 51.

The spelling of 21699439512 in words is "twenty-one billion, six hundred ninety-nine million, four hundred thirty-nine thousand, five hundred twelve".