101020000021 has 4 divisors (see below), whose sum is σ = 101206728844. Its totient is φ = 100833271200.

The previous prime is 101019999991. The next prime is 101020000051. The reversal of 101020000021 is 120000020101.

It is a semiprime because it is the product of two primes.

It is an interprime number because it is at equal distance from previous prime (101019999991) and next prime (101020000051).

It can be written as a sum of positive squares in 2 ways, for example, as 79997899921 + 21022100100 = 282839^2 + 144990^2 .

It is a cyclic number.

It is not a de Polignac number, because 101020000021 - 2¹³ = 101019991829 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 101019999959 and 101020000013.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (101020000051) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 93363600 + ... + 93364681.

It is an arithmetic number, because the mean of its divisors is an integer number (25301682211).

Almost surely, 2^101020000021 is an apocalyptic number.

It is an amenable number.

101020000021 is a deficient number, since it is larger than the sum of its proper divisors (186728823).

101020000021 is an equidigital number, since it uses as much as digits as its factorization.

101020000021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 186728822.

The product of its (nonzero) digits is 4, while the sum is 7.

Adding to 101020000021 its reverse (120000020101), we get a palindrome (221020020122).

The spelling of 101020000021 in words is "one hundred one billion, twenty million, twenty-one", and thus it is an aban number.