21042171432 has 96 divisors (see below), whose sum is σ = 59890939680. Its totient is φ = 6665742720.

The previous prime is 21042171421. The next prime is 21042171457. The reversal of 21042171432 is 23417124012.

21042171432 is a `hidden beast` number, since 2 + 10 + 4 + 217 + 1 + 432 = 666.

It is a junction number, because it is equal to n+sod(n) for n = 21042171396 and 21042171405.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 22707 + ... + 206397.

It is an arithmetic number, because the mean of its divisors is an integer number (623863955).

Almost surely, 2^21042171432 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 21042171432, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (29945469840).

21042171432 is an abundant number, since it is smaller than the sum of its proper divisors (38848768248).

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

21042171432 is a wasteful number, since it uses less digits than its factorization.

21042171432 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 183783 (or 183776 counting only the distinct ones).

The product of its (nonzero) digits is 2688, while the sum is 27.

Adding to 21042171432 its reverse (23417124012), we get a palindrome (44459295444).

The spelling of 21042171432 in words is "twenty-one billion, forty-two million, one hundred seventy-one thousand, four hundred thirty-two".