20122001 has 4 divisors (see below), whose sum is σ = 20210100. Its totient is φ = 20033904.

The previous prime is 20121989. The next prime is 20122031. The reversal of 20122001 is 10022102.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 10022102 = 2 ⋅5011051.

It can be written as a sum of positive squares in 2 ways, for example, as 9461776 + 10660225 = 3076^2 + 3265^2 .

It is a cyclic number.

It is not a de Polignac number, because 20122001 - 2¹⁸ = 19859857 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 20122001.

It is not an unprimeable number, because it can be changed into a prime (20122031) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 43706 + ... + 44163.

It is an arithmetic number, because the mean of its divisors is an integer number (5052525).

Almost surely, 2^20122001 is an apocalyptic number.

It is an amenable number.

20122001 is a deficient number, since it is larger than the sum of its proper divisors (88099).

20122001 is an equidigital number, since it uses as much as digits as its factorization.

20122001 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 88098.

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

The square root of 20122001 is about 4485.7553433062. The cubic root of 20122001 is about 271.9925792742.

Adding to 20122001 its reverse (10022102), we get a palindrome (30144103).

The spelling of 20122001 in words is "twenty million, one hundred twenty-two thousand, one".