21037011256 has 16 divisors (see below), whose sum is σ = 39500040600. Its totient is φ = 10503667104.

The previous prime is 21037011251. The next prime is 21037011283. The reversal of 21037011256 is 65211073012.

It is a happy number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21037011251) 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, 1848790 + ... + 1860133.

Almost surely, 2^21037011256 is an apocalyptic number.

It is an amenable number.

21037011256 is a deficient number, since it is larger than the sum of its proper divisors (18463029344).

21037011256 is a wasteful number, since it uses less digits than its factorization.

21037011256 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3709638 (or 3709634 counting only the distinct ones).

The product of its (nonzero) digits is 2520, while the sum is 28.

Adding to 21037011256 its reverse (65211073012), we get a palindrome (86248084268).

The spelling of 21037011256 in words is "twenty-one billion, thirty-seven million, eleven thousand, two hundred fifty-six".