21011012176 has 160 divisors (see below), whose sum is σ = 52078381056. Its totient is φ = 7974720000.

The previous prime is 21011012161. The next prime is 21011012177. The reversal of 21011012176 is 67121011012.

It is a Harshad number since it is a multiple of its sum of digits (22).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21011012177) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 9858631 + ... + 9860761.

Almost surely, 2^21011012176 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21011012176, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (26039190528).

21011012176 is an abundant number, since it is smaller than the sum of its proper divisors (31067368880).

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

21011012176 is a wasteful number, since it uses less digits than its factorization.

21011012176 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2361 (or 2355 counting only the distinct ones).

The product of its (nonzero) digits is 168, while the sum is 22.

Adding to 21011012176 its reverse (67121011012), we get a palindrome (88132023188).

The spelling of 21011012176 in words is "twenty-one billion, eleven million, twelve thousand, one hundred seventy-six".