20101000221 has 12 divisors (see below), whose sum is σ = 29526893760. Its totient is φ = 13173536520.

The previous prime is 20101000207. The next prime is 20101000223. The reversal of 20101000221 is 12200010102.

It is not a de Polignac number, because 20101000221 - 2⁵ = 20101000189 is a prime.

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20101000223) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 18926965 + ... + 18928026.

It is an arithmetic number, because the mean of its divisors is an integer number (2460574480).

Almost surely, 2^20101000221 is an apocalyptic number.

It is an amenable number.

20101000221 is a deficient number, since it is larger than the sum of its proper divisors (9425893539).

20101000221 is a wasteful number, since it uses less digits than its factorization.

20101000221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 37855056 (or 37855053 counting only the distinct ones).

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

Adding to 20101000221 its reverse (12200010102), we get a palindrome (32301010323).

The spelling of 20101000221 in words is "twenty billion, one hundred one million, two hundred twenty-one", and thus it is an aban number.