21020102273 has 2 divisors, whose sum is σ = 21020102274. Its totient is φ = 21020102272.

The previous prime is 21020102143. The next prime is 21020102291. The reversal of 21020102273 is 37220102012.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 20938958209 + 81144064 = 144703^2 + 9008^2 .

It is a cyclic number.

It is not a de Polignac number, because 21020102273 - 2²⁰ = 21019053697 is a prime.

It is not a weakly prime, because it can be changed into another prime (21020702273) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10510051136 + 10510051137.

It is an arithmetic number, because the mean of its divisors is an integer number (10510051137).

Almost surely, 2^21020102273 is an apocalyptic number.

It is an amenable number.

21020102273 is a deficient number, since it is larger than the sum of its proper divisors (1).

21020102273 is an equidigital number, since it uses as much as digits as its factorization.

21020102273 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 336, while the sum is 20.

Adding to 21020102273 its reverse (37220102012), we get a palindrome (58240204285).

The spelling of 21020102273 in words is "twenty-one billion, twenty million, one hundred two thousand, two hundred seventy-three".