102100101021 has 32 divisors (see below), whose sum is σ = 159232792320. Its totient is φ = 64531095552.

The previous prime is 102100101007. The next prime is 102100101023. The reversal of 102100101021 is 120101001201.

It is a happy number.

It is a de Polignac number, because none of the positive numbers 2^k-102100101021 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (9).

It is a junction number, because it is equal to n+sod(n) for n = 102100100994 and 102100101012.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (102100101023) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 657316 + ... + 797661.

It is an arithmetic number, because the mean of its divisors is an integer number (4976024760).

Almost surely, 2^102100101021 is an apocalyptic number.

It is an amenable number.

102100101021 is a deficient number, since it is larger than the sum of its proper divisors (57132691299).

102100101021 is a wasteful number, since it uses less digits than its factorization.

102100101021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1455122 (or 1455116 counting only the distinct ones).

The product of its (nonzero) digits is 4, while the sum is 9.

Adding to 102100101021 its reverse (120101001201), we get a palindrome (222201102222).

The spelling of 102100101021 in words is "one hundred two billion, one hundred million, one hundred one thousand, twenty-one".