101210000021 has 16 divisors (see below), whose sum is σ = 116428206384. Its totient is φ = 87150895104.

The previous prime is 101209999999. The next prime is 101210000107. The reversal of 101210000021 is 120000012101.

It can be written as a sum of positive squares in 8 ways, for example, as 26564110225 + 74645889796 = 162985^2 + 273214^2 .

It is not a de Polignac number, because 101210000021 - 2³⁰ = 100136258197 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 101209999963 and 101210000008.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (101210000321) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 2001416 + ... + 2051361.

It is an arithmetic number, because the mean of its divisors is an integer number (7276762899).

Almost surely, 2^101210000021 is an apocalyptic number.

It is an amenable number.

101210000021 is a deficient number, since it is larger than the sum of its proper divisors (15218206363).

101210000021 is a wasteful number, since it uses less digits than its factorization.

101210000021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4052920.

The product of its (nonzero) digits is 4, while the sum is 8.

Adding to 101210000021 its reverse (120000012101), we get a palindrome (221210012122).

The spelling of 101210000021 in words is "one hundred one billion, two hundred ten million, twenty-one", and thus it is an aban number.