20021102001 has 12 divisors (see below), whose sum is σ = 29624720580. Its totient is φ = 13021854720.

The previous prime is 20021101981. The next prime is 20021102027. The reversal of 20021102001 is 10020112002.

It can be written as a sum of positive squares in 2 ways, for example, as 1374926400 + 18646175601 = 37080^2 + 136551^2 .

It is not a de Polignac number, because 20021102001 - 2⁹ = 20021101489 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (9).

It is not an unprimeable number, because it can be changed into a prime (20021102401) 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 11 ways as a sum of consecutive naturals, for example, 27128496 + ... + 27129233.

It is an arithmetic number, because the mean of its divisors is an integer number (2468726715).

Almost surely, 2^20021102001 is an apocalyptic number.

It is an amenable number.

20021102001 is a deficient number, since it is larger than the sum of its proper divisors (9603618579).

20021102001 is a wasteful number, since it uses less digits than its factorization.

20021102001 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 54257776 (or 54257773 counting only the distinct ones).

The product of its (nonzero) digits is 8, while the sum is 9.

Adding to 20021102001 its reverse (10020112002), we get a palindrome (30041214003).

The spelling of 20021102001 in words is "twenty billion, twenty-one million, one hundred two thousand, one".