102111211021 has 2 divisors, whose sum is σ = 102111211022. Its totient is φ = 102111211020.

The previous prime is 102111210973. The next prime is 102111211051. The reversal of 102111211021 is 120112111201.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 98388868900 + 3722342121 = 313670^2 + 61011^2 .

It is a cyclic number.

It is not a de Polignac number, because 102111211021 - 2¹¹ = 102111208973 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 102111210992 and 102111211010.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (102111211051) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 51055605510 + 51055605511.

It is an arithmetic number, because the mean of its divisors is an integer number (51055605511).

Almost surely, 2^102111211021 is an apocalyptic number.

It is an amenable number.

102111211021 is a deficient number, since it is larger than the sum of its proper divisors (1).

102111211021 is an equidigital number, since it uses as much as digits as its factorization.

102111211021 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 8, while the sum is 13.

Adding to 102111211021 its reverse (120112111201), we get a palindrome (222223322222).

The spelling of 102111211021 in words is "one hundred two billion, one hundred eleven million, two hundred eleven thousand, twenty-one".