21506142715072 has 112 divisors (see below), whose sum is σ = 45641114053632. Its totient is φ = 10030871459840.

The previous prime is 21506142715069. The next prime is 21506142715091. The reversal of 21506142715072 is 27051724160512.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 18887583 + ... + 19993825.

Almost surely, 2^{21506142715072} 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 21506142715072, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (22820557026816).

21506142715072 is an abundant number, since it is smaller than the sum of its proper divisors (24134971338560).

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

21506142715072 is a wasteful number, since it uses less digits than its factorization.

21506142715072 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1106606 (or 1106596 counting only the distinct ones).

The product of its (nonzero) digits is 235200, while the sum is 43.

Adding to 21506142715072 its reverse (27051724160512), we get a palindrome (48557866875584).

The spelling of 21506142715072 in words is "twenty-one trillion, five hundred six billion, one hundred forty-two million, seven hundred fifteen thousand, seventy-two".