21404432112 has 160 divisors (see below), whose sum is σ = 66208333824. Its totient is φ = 5829753600.

The previous prime is 21404432059. The next prime is 21404432117. The reversal of 21404432112 is 21123440412.

It is a Harshad number since it is a multiple of its sum of digits (24).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21404432117) 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, 682537 + ... + 713207.

Almost surely, 2^21404432112 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 21404432112, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (33104166912).

21404432112 is an abundant number, since it is smaller than the sum of its proper divisors (44803901712).

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

21404432112 is a wasteful number, since it uses less digits than its factorization.

21404432112 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 30787 (or 30781 counting only the distinct ones).

The product of its (nonzero) digits is 1536, while the sum is 24.

Adding to 21404432112 its reverse (21123440412), we get a palindrome (42527872524).

The spelling of 21404432112 in words is "twenty-one billion, four hundred four million, four hundred thirty-two thousand, one hundred twelve".