20001121632 has 288 divisors, whose sum is σ = 61666375680. Its totient is φ = 6131220480.

The previous prime is 20001121597. The next prime is 20001121687. The reversal of 20001121632 is 23612110002.

20001121632 is a `hidden beast` number, since 2 + 0 + 0 + 0 + 11 + 21 + 632 = 666.

It is a tau number, because it is divible by the number of its divisors (288).

It is a Harshad number since it is a multiple of its sum of digits (18).

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 52773219 + ... + 52773597.

It is an arithmetic number, because the mean of its divisors is an integer number (214119360).

Almost surely, 2^20001121632 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 20001121632, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (30833187840).

20001121632 is an abundant number, since it is smaller than the sum of its proper divisors (41665254048).

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

20001121632 is a wasteful number, since it uses less digits than its factorization.

20001121632 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 706 (or 695 counting only the distinct ones).

The product of its (nonzero) digits is 144, while the sum is 18.

Adding to 20001121632 its reverse (23612110002), we get a palindrome (43613231634).

The spelling of 20001121632 in words is "twenty billion, one million, one hundred twenty-one thousand, six hundred thirty-two".