20001002001 has 4 divisors (see below), whose sum is σ = 26668002672. Its totient is φ = 13334001332.

The previous prime is 20001001957. The next prime is 20001002029. The reversal of 20001002001 is 10020010002.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 20001002001 - 2⁷ = 20001001873 is a prime.

It is not an unprimeable number, because it can be changed into a prime (20001002201) 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, 3333500331 + ... + 3333500336.

It is an arithmetic number, because the mean of its divisors is an integer number (6667000668).

Almost surely, 2^20001002001 is an apocalyptic number.

It is an amenable number.

20001002001 is a deficient number, since it is larger than the sum of its proper divisors (6667000671).

20001002001 is an equidigital number, since it uses as much as digits as its factorization.

20001002001 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6667000670.

The product of its (nonzero) digits is 4, while the sum is 6.

Adding to 20001002001 its reverse (10020010002), we get a palindrome (30021012003).

It can be divided in two parts, 2000 and 1002001, that added together give a palindrome (1004001).

The spelling of 20001002001 in words is "twenty billion, one million, two thousand, one".