21620734205120 has 56 divisors (see below), whose sum is σ = 51956707110000. Its totient is φ = 8568951524352.

The previous prime is 21620734205117. The next prime is 21620734205209. The reversal of 21620734205120 is 2150243702612.

It is a super-2 number, since 2×21620734205120² (a number of 27 digits) contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 309895370 + ... + 309965129.

It is an arithmetic number, because the mean of its divisors is an integer number (927798341250).

Almost surely, 2^{21620734205120} is an apocalyptic number.

21620734205120 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21620734205120 is an abundant number, since it is smaller than the sum of its proper divisors (30335972904880).

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

21620734205120 is a wasteful number, since it uses less digits than its factorization.

21620734205120 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 619860625 (or 619860615 counting only the distinct ones).

The product of its (nonzero) digits is 40320, while the sum is 35.

Adding to 21620734205120 its reverse (2150243702612), we get a palindrome (23770977907732).

The spelling of 21620734205120 in words is "twenty-one trillion, six hundred twenty billion, seven hundred thirty-four million, two hundred five thousand, one hundred twenty".