21443431212 has 48 divisors (see below), whose sum is σ = 63536094720. Its totient is φ = 6126694416.

The previous prime is 21443431201. The next prime is 21443431267. The reversal of 21443431212 is 21213434412.

21443431212 is a `hidden beast` number, since 2 + 1 + 443 + 4 + 3 + 1 + 212 = 666.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a nude number because it is divisible by every one of its digits.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 14181408 + ... + 14182919.

It is an arithmetic number, because the mean of its divisors is an integer number (1323668640).

Almost surely, 2^21443431212 is an apocalyptic number.

It is an amenable number.

21443431212 is an abundant number, since it is smaller than the sum of its proper divisors (42092663508).

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

21443431212 is a wasteful number, since it uses less digits than its factorization.

21443431212 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 28364347 (or 28364339 counting only the distinct ones).

The product of its digits is 4608, while the sum is 27.

Adding to 21443431212 its reverse (21213434412), we get a palindrome (42656865624).

The spelling of 21443431212 in words is "twenty-one billion, four hundred forty-three million, four hundred thirty-one thousand, two hundred twelve".