21120000020001 has 32 divisors (see below), whose sum is σ = 33133412632320. Its totient is φ = 13250164384512.

The previous prime is 21120000019969. The next prime is 21120000020017. The reversal of 21120000020001 is 10002000002112.

It is not a de Polignac number, because 21120000020001 - 2⁵ = 21120000019969 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (9).

It is not an unprimeable number, because it can be changed into a prime (21120000020701) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 1032276 + ... + 6580698.

It is an arithmetic number, because the mean of its divisors is an integer number (1035419144760).

Almost surely, 2^{21120000020001} is an apocalyptic number.

It is an amenable number.

21120000020001 is a deficient number, since it is larger than the sum of its proper divisors (12013412612319).

21120000020001 is a wasteful number, since it uses less digits than its factorization.

21120000020001 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5556742 (or 5556736 counting only the distinct ones).

The product of its (nonzero) digits is 8, while the sum is 9.

Adding to 21120000020001 its reverse (10002000002112), we get a palindrome (31122000022113).

The spelling of 21120000020001 in words is "twenty-one trillion, one hundred twenty billion, twenty thousand, one".