21121403126634 has 192 divisors, whose sum is σ = 48477282796800. Its totient is φ = 6636978432000.

The previous prime is 21121403126611. The next prime is 21121403126669. The reversal of 21121403126634 is 43662130412112.

21121403126634 is a `hidden beast` number, since 2 + 1 + 1 + 2 + 1 + 4 + 0 + 3 + 12 + 6 + 634 = 666.

It is a super-2 number, since 2×21121403126634² (a number of 27 digits) contains 22 as substring.

It is a Curzon number.

It is an unprimeable number.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 1308710137 + ... + 1308726275.

It is an arithmetic number, because the mean of its divisors is an integer number (252485847900).

Almost surely, 2^{21121403126634} is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21121403126634, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (24238641398400).

21121403126634 is an abundant number, since it is smaller than the sum of its proper divisors (27355879670166).

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

21121403126634 is a wasteful number, since it uses less digits than its factorization.

21121403126634 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 16621 (or 16618 counting only the distinct ones).

The product of its (nonzero) digits is 41472, while the sum is 36.

Adding to 21121403126634 its reverse (43662130412112), we get a palindrome (64783533538746).

The spelling of 21121403126634 in words is "twenty-one trillion, one hundred twenty-one billion, four hundred three million, one hundred twenty-six thousand, six hundred thirty-four".