21122004312 has 64 divisors (see below), whose sum is σ = 58970181600. Its totient is φ = 7004914560.

The previous prime is 21122004289. The next prime is 21122004313. The reversal of 21122004312 is 21340022112.

It is a happy number.

21122004312 is a `hidden beast` number, since 2 + 11 + 220 + 0 + 431 + 2 = 666.

It is a super-2 number, since 2×21122004312² (a number of 21 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (18).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21122004313) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 205639 + ... + 290742.

Almost surely, 2^21122004312 is an apocalyptic number.

It is an amenable number.

21122004312 is an abundant number, since it is smaller than the sum of its proper divisors (37848177288).

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

21122004312 is a wasteful number, since it uses less digits than its factorization.

21122004312 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 496593 (or 496583 counting only the distinct ones).

The product of its (nonzero) digits is 192, while the sum is 18.

Adding to 21122004312 its reverse (21340022112), we get a palindrome (42462026424).

The spelling of 21122004312 in words is "twenty-one billion, one hundred twenty-two million, four thousand, three hundred twelve".