21112020010001 has 4 divisors (see below), whose sum is σ = 21112606865892. Its totient is φ = 21111433154112.

The previous prime is 21112020009973. The next prime is 21112020010007. The reversal of 21112020010001 is 10001002021112.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 13912452403600 + 7199567606401 = 3729940^2 + 2683201^2 .

It is a cyclic number.

It is not a de Polignac number, because 21112020010001 - 2¹⁸ = 21112019747857 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21112020010007) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 293373980 + ... + 293445933.

It is an arithmetic number, because the mean of its divisors is an integer number (5278151716473).

Almost surely, 2^{21112020010001} is an apocalyptic number.

It is an amenable number.

21112020010001 is a deficient number, since it is larger than the sum of its proper divisors (586855891).

21112020010001 is an equidigital number, since it uses as much as digits as its factorization.

21112020010001 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 586855890.

The product of its (nonzero) digits is 8, while the sum is 11.

Adding to 21112020010001 its reverse (10001002021112), we get a palindrome (31113022031113).

The spelling of 21112020010001 in words is "twenty-one trillion, one hundred twelve billion, twenty million, ten thousand, one".