102102120021 has 32 divisors (see below), whose sum is σ = 150502809600. Its totient is φ = 61051798080.

The previous prime is 102102120017. The next prime is 102102120031. The reversal of 102102120021 is 120021201201.

It is not a de Polignac number, because 102102120021 - 2² = 102102120017 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 102102119979 and 102102120006.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (102102120031) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 3711700 + ... + 3739106.

It is an arithmetic number, because the mean of its divisors is an integer number (4703212800).

Almost surely, 2^102102120021 is an apocalyptic number.

102102120021 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

102102120021 is a deficient number, since it is larger than the sum of its proper divisors (48400689579).

102102120021 is a wasteful number, since it uses less digits than its factorization.

102102120021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 28929.

The product of its (nonzero) digits is 16, while the sum is 12.

Adding to 102102120021 its reverse (120021201201), we get a palindrome (222123321222).

The spelling of 102102120021 in words is "one hundred two billion, one hundred two million, one hundred twenty thousand, twenty-one".