20211001001 has 16 divisors (see below), whose sum is σ = 21284640000. Its totient is φ = 19163174016.

The previous prime is 20211000991. The next prime is 20211001003. The reversal of 20211001001 is 10010011202.

It is not a de Polignac number, because 20211001001 - 2¹⁴ = 20210984617 is a prime.

It is a super-2 number, since 2×20211001001² (a number of 21 digits) contains 22 as substring.

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 20211001001.

It is not an unprimeable number, because it can be changed into a prime (20211001003) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1772045 + ... + 1783413.

It is an arithmetic number, because the mean of its divisors is an integer number (1330290000).

Almost surely, 2^20211001001 is an apocalyptic number.

It is an amenable number.

20211001001 is a deficient number, since it is larger than the sum of its proper divisors (1073638999).

20211001001 is a wasteful number, since it uses less digits than its factorization.

20211001001 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12496.

The product of its (nonzero) digits is 4, while the sum is 8.

Adding to 20211001001 its reverse (10010011202), we get a palindrome (30221012203).

The spelling of 20211001001 in words is "twenty billion, two hundred eleven million, one thousand, one".