102111221021 has 8 divisors (see below), whose sum is σ = 108294149304. Its totient is φ = 95947891200.

The previous prime is 102111220949. The next prime is 102111221027. The reversal of 102111221021 is 120122111201.

It can be written as a sum of positive squares in 4 ways, for example, as 11578836025 + 90532384996 = 107605^2 + 300886^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 102111221021 - 2¹⁸ = 102110958877 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 102111220987 and 102111221005.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (102111221027) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 4888880 + ... + 4909721.

It is an arithmetic number, because the mean of its divisors is an integer number (13536768663).

Almost surely, 2^102111221021 is an apocalyptic number.

It is an amenable number.

102111221021 is a deficient number, since it is larger than the sum of its proper divisors (6182928283).

102111221021 is an equidigital number, since it uses as much as digits as its factorization.

102111221021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9799231.

The product of its (nonzero) digits is 16, while the sum is 14.

Adding to 102111221021 its reverse (120122111201), we get a palindrome (222233332222).

The spelling of 102111221021 in words is "one hundred two billion, one hundred eleven million, two hundred twenty-one thousand, twenty-one".