21121100010101 has 24 divisors (see below), whose sum is σ = 28015835321880. Its totient is φ = 15728188234752.

The previous prime is 21121100010083. The next prime is 21121100010133. The reversal of 21121100010101 is 10101000112112.

It can be written as a sum of positive squares in 4 ways, for example, as 6003117415876 + 15117982594225 = 2450126^2 + 3888185^2 .

It is not a de Polignac number, because 21121100010101 - 2⁶ = 21121100010037 is a prime.

It is a super-2 number, since 2×21121100010101² (a number of 27 digits) contains 22 as substring.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21121100010161) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 975199256 + ... + 975220913.

It is an arithmetic number, because the mean of its divisors is an integer number (1167326471745).

Almost surely, 2^{21121100010101} is an apocalyptic number.

It is an amenable number.

21121100010101 is a deficient number, since it is larger than the sum of its proper divisors (6894735311779).

21121100010101 is a wasteful number, since it uses less digits than its factorization.

21121100010101 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1950420213 (or 1950420206 counting only the distinct ones).

The product of its (nonzero) digits is 4, while the sum is 11.

Adding to 21121100010101 its reverse (10101000112112), we get a palindrome (31222100122213).

The spelling of 21121100010101 in words is "twenty-one trillion, one hundred twenty-one billion, one hundred million, ten thousand, one hundred one".