21601673237172 has 288 divisors, whose sum is σ = 61399704457728. Its totient is φ = 5888804253696.

The previous prime is 21601673237167. The next prime is 21601673237213. The reversal of 21601673237172 is 27173237610612.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 229912188 + ... + 230006124.

It is an arithmetic number, because the mean of its divisors is an integer number (213193418256).

Almost surely, 2^{21601673237172} 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 21601673237172, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (30699852228864).

21601673237172 is an abundant number, since it is smaller than the sum of its proper divisors (39798031220556).

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

21601673237172 is a wasteful number, since it uses less digits than its factorization.

21601673237172 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 94215 (or 94206 counting only the distinct ones).

The product of its (nonzero) digits is 889056, while the sum is 48.

The spelling of 21601673237172 in words is "twenty-one trillion, six hundred one billion, six hundred seventy-three million, two hundred thirty-seven thousand, one hundred seventy-two".