21023205615522 has 96 divisors (see below), whose sum is σ = 50140643245056. Its totient is φ = 6313070937600.

The previous prime is 21023205615499. The next prime is 21023205615523. The reversal of 21023205615522 is 22551650232012.

21023205615522 is a `hidden beast` number, since 2 + 1 + 0 + 2 + 3 + 20 + 561 + 55 + 22 = 666.

It is not an unprimeable number, because it can be changed into a prime (21023205615523) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 119232447 + ... + 119408637.

It is an arithmetic number, because the mean of its divisors is an integer number (522298367136).

Almost surely, 2^{21023205615522} is an apocalyptic number.

21023205615522 is a gapful number since it is divisible by the number (22) formed by its first and last digit.

It is a practical number, because each smaller number is the sum of distinct divisors of 21023205615522, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (25070321622528).

21023205615522 is an abundant number, since it is smaller than the sum of its proper divisors (29117437629534).

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

21023205615522 is a wasteful number, since it uses less digits than its factorization.

21023205615522 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 181656 (or 181653 counting only the distinct ones).

The product of its (nonzero) digits is 72000, while the sum is 36.

Adding to 21023205615522 its reverse (22551650232012), we get a palindrome (43574855847534).

The spelling of 21023205615522 in words is "twenty-one trillion, twenty-three billion, two hundred five million, six hundred fifteen thousand, five hundred twenty-two".