21551134522104 has 288 divisors, whose sum is σ = 65500016858640. Its totient is φ = 6348435609600.

The previous prime is 21551134522087. The next prime is 21551134522109. The reversal of 21551134522104 is 40122543115512.

21551134522104 is a `hidden beast` number, since 2 + 1 + 5 + 5 + 113 + 4 + 522 + 10 + 4 = 666.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21551134522109) by changing a digit.

It is a polite number, since it can be written in 71 ways as a sum of consecutive naturals, for example, 1293499534 + ... + 1293516194.

Almost surely, 2^{21551134522104} is an apocalyptic number.

21551134522104 is a gapful number since it is divisible by the number (24) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21551134522104, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (32750008429320).

21551134522104 is an abundant number, since it is smaller than the sum of its proper divisors (43948882336536).

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

21551134522104 is a wasteful number, since it uses less digits than its factorization.

21551134522104 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 17951 (or 17907 counting only the distinct ones).

The product of its (nonzero) digits is 48000, while the sum is 36.

Adding to 21551134522104 its reverse (40122543115512), we get a palindrome (61673677637616).

The spelling of 21551134522104 in words is "twenty-one trillion, five hundred fifty-one billion, one hundred thirty-four million, five hundred twenty-two thousand, one hundred four".