101020100000021 has 4 divisors (see below), whose sum is σ = 101239232538444. Its totient is φ = 100800967461600.

The previous prime is 101020100000003. The next prime is 101020100000041. The reversal of 101020100000021 is 120000001020101.

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

It can be written as a sum of positive squares in 2 ways, for example, as 50982670246225 + 50037429753796 = 7140215^2 + 7073714^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-101020100000021 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 101020099999954 and 101020100000008.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (101020100000041) 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, 109566268520 + ... + 109566269441.

It is an arithmetic number, because the mean of its divisors is an integer number (25309808134611).

Almost surely, 2^{101020100000021} is an apocalyptic number.

It is an amenable number.

101020100000021 is a deficient number, since it is larger than the sum of its proper divisors (219132538423).

101020100000021 is an equidigital number, since it uses as much as digits as its factorization.

101020100000021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 219132538422.

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

Adding to 101020100000021 its reverse (120000001020101), we get a palindrome (221020101020122).

The spelling of 101020100000021 in words is "one hundred one trillion, twenty billion, one hundred million, twenty-one", and thus it is an aban number.