21120012101 has 8 divisors (see below), whose sum is σ = 22433816664. Its totient is φ = 19814146560.

The previous prime is 21120012097. The next prime is 21120012107. The reversal of 21120012101 is 10121002112.

It can be written as a sum of positive squares in 4 ways, for example, as 1729728100 + 19390284001 = 41590^2 + 139249^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 21120012101 - 2² = 21120012097 is a prime.

It is a super-2 number, since 2×21120012101² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21120012107) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1979270 + ... + 1989911.

It is an arithmetic number, because the mean of its divisors is an integer number (2804227083).

Almost surely, 2^21120012101 is an apocalyptic number.

It is an amenable number.

21120012101 is a deficient number, since it is larger than the sum of its proper divisors (1313804563).

21120012101 is a wasteful number, since it uses less digits than its factorization.

21120012101 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3969511.

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

Adding to 21120012101 its reverse (10121002112), we get a palindrome (31241014213).

The spelling of 21120012101 in words is "twenty-one billion, one hundred twenty million, twelve thousand, one hundred one".