20101210101 has 32 divisors (see below), whose sum is σ = 34040448000. Its totient is φ = 11484160560.

The previous prime is 20101210099. The next prime is 20101210121. The reversal of 20101210101 is 10101210102.

It is a happy number.

It is not a de Polignac number, because 20101210101 - 2¹ = 20101210099 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 (20101210121) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 1712350 + ... + 1724048.

It is an arithmetic number, because the mean of its divisors is an integer number (1063764000).

Almost surely, 2^20101210101 is an apocalyptic number.

20101210101 is a gapful number since it is divisible by the number (21) formed by its first and last digit.

It is an amenable number.

20101210101 is a deficient number, since it is larger than the sum of its proper divisors (13939237899).

20101210101 is a wasteful number, since it uses less digits than its factorization.

20101210101 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 20806 (or 20800 counting only the distinct ones).

The product of its (nonzero) digits is 4, while the sum is 9.

Adding to 20101210101 its reverse (10101210102), we get a palindrome (30202420203).

Subtracting from 20101210101 its reverse (10101210102), we obtain a palindrome (9999999999).

The spelling of 20101210101 in words is "twenty billion, one hundred one million, two hundred ten thousand, one hundred one".