102112100021 has 4 divisors (see below), whose sum is σ = 102396535200. Its totient is φ = 101827664844.

The previous prime is 102112099997. The next prime is 102112100053. The reversal of 102112100021 is 120001211201.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 120001211201 = 29009 ⋅4136689.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-102112100021 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 102112099975 and 102112100011.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (102112120021) 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, 142217051 + ... + 142217768.

It is an arithmetic number, because the mean of its divisors is an integer number (25599133800).

Almost surely, 2^102112100021 is an apocalyptic number.

It is an amenable number.

102112100021 is a deficient number, since it is larger than the sum of its proper divisors (284435179).

102112100021 is an equidigital number, since it uses as much as digits as its factorization.

102112100021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 284435178.

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

Adding to 102112100021 its reverse (120001211201), we get a palindrome (222113311222).

The spelling of 102112100021 in words is "one hundred two billion, one hundred twelve million, one hundred thousand, twenty-one".