21120210101 has 4 divisors (see below), whose sum is σ = 21120914304. Its totient is φ = 21119505900.

The previous prime is 21120210079. The next prime is 21120210107. The reversal of 21120210101 is 10101202112.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 21120210101 - 2²² = 21116015797 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21120210107) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 305015 + ... + 367796.

It is an arithmetic number, because the mean of its divisors is an integer number (5280228576).

Almost surely, 2^21120210101 is an apocalyptic number.

It is an amenable number.

21120210101 is a deficient number, since it is larger than the sum of its proper divisors (704203).

21120210101 is an equidigital number, since it uses as much as digits as its factorization.

21120210101 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 704202.

The product of its (nonzero) digits is 8, while the sum is 11.

Adding to 21120210101 its reverse (10101202112), we get a palindrome (31221412213).

The spelling of 21120210101 in words is "twenty-one billion, one hundred twenty million, two hundred ten thousand, one hundred one".