21556441132422 has 128 divisors (see below), whose sum is σ = 52812565263360. Its totient is φ = 5725591449600.

The previous prime is 21556441132417. The next prime is 21556441132463. The reversal of 21556441132422 is 22423114465512.

It is a Harshad number since it is a multiple of its sum of digits (42).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 29859058 + ... + 30572474.

It is an arithmetic number, because the mean of its divisors is an integer number (412598166120).

Almost surely, 2^{21556441132422} is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21556441132422, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (26406282631680).

21556441132422 is an abundant number, since it is smaller than the sum of its proper divisors (31256124130938).

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

21556441132422 is a wasteful number, since it uses less digits than its factorization.

21556441132422 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 713966.

The product of its digits is 460800, while the sum is 42.

Adding to 21556441132422 its reverse (22423114465512), we get a palindrome (43979555597934).

The spelling of 21556441132422 in words is "twenty-one trillion, five hundred fifty-six billion, four hundred forty-one million, one hundred thirty-two thousand, four hundred twenty-two".