21006210512 has 40 divisors (see below), whose sum is σ = 46868851392. Its totient is φ = 8933932800.

The previous prime is 21006210499. The next prime is 21006210539. The reversal of 21006210512 is 21501260012.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 701189 + ... + 730532.

Almost surely, 2^21006210512 is an apocalyptic number.

It is an amenable number.

21006210512 is an abundant number, since it is smaller than the sum of its proper divisors (25862640880).

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

21006210512 is a wasteful number, since it uses less digits than its factorization.

21006210512 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1431867 (or 1431861 counting only the distinct ones).

The product of its (nonzero) digits is 240, while the sum is 20.

Adding to 21006210512 its reverse (21501260012), we get a palindrome (42507470524).

The spelling of 21006210512 in words is "twenty-one billion, six million, two hundred ten thousand, five hundred twelve".