20021001001 has 8 divisors (see below), whose sum is σ = 20194634624. Its totient is φ = 19847987280.

The previous prime is 20021000981. The next prime is 20021001029. The reversal of 20021001001 is 10010012002.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 20021001001 - 2¹³ = 20020992809 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20021001401) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 89985 + ... + 219406.

It is an arithmetic number, because the mean of its divisors is an integer number (2524329328).

Almost surely, 2^20021001001 is an apocalyptic number.

It is an amenable number.

20021001001 is a deficient number, since it is larger than the sum of its proper divisors (173633623).

20021001001 is a wasteful number, since it uses less digits than its factorization.

20021001001 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 309951.

The product of its (nonzero) digits is 4, while the sum is 7.

Adding to 20021001001 its reverse (10010012002), we get a palindrome (30031013003).

It can be divided in two parts, 2002 and 1001001, that multiplied together give a palindrome (2004004002).

The spelling of 20021001001 in words is "twenty billion, twenty-one million, one thousand, one".