21655405301252 has 12 divisors (see below), whose sum is σ = 39544653158976. Its totient is φ = 10356932970120.

The previous prime is 21655405301251. The next prime is 21655405301363. The reversal of 21655405301252 is 25210350455612.

It is a super-2 number, since 2×21655405301252² (a number of 27 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (21655405301251) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 117692420024 + ... + 117692420207.

It is an arithmetic number, because the mean of its divisors is an integer number (3295387763248).

Almost surely, 2^{21655405301252} is an apocalyptic number.

It is an amenable number.

21655405301252 is a deficient number, since it is larger than the sum of its proper divisors (17889247857724).

21655405301252 is a wasteful number, since it uses less digits than its factorization.

21655405301252 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 235384840258 (or 235384840256 counting only the distinct ones).

The product of its (nonzero) digits is 360000, while the sum is 41.

Adding to 21655405301252 its reverse (25210350455612), we get a palindrome (46865755756864).

The spelling of 21655405301252 in words is "twenty-one trillion, six hundred fifty-five billion, four hundred five million, three hundred one thousand, two hundred fifty-two".