20102689 has 2 divisors, whose sum is σ = 20102690. Its totient is φ = 20102688.

The previous prime is 20102671. The next prime is 20102701. The reversal of 20102689 is 98620102.

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., 19936225 + 166464 = 4465^2 + 408^2 .

It is a cyclic number.

It is not a de Polignac number, because 20102689 - 2¹³ = 20094497 is a prime.

It is not a weakly prime, because it can be changed into another prime (20102609) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10051344 + 10051345.

It is an arithmetic number, because the mean of its divisors is an integer number (10051345).

Almost surely, 2^20102689 is an apocalyptic number.

It is an amenable number.

20102689 is a deficient number, since it is larger than the sum of its proper divisors (1).

20102689 is an equidigital number, since it uses as much as digits as its factorization.

20102689 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1728, while the sum is 28.

The square root of 20102689 is about 4483.6022348108. The cubic root of 20102689 is about 271.9055368703.

The spelling of 20102689 in words is "twenty million, one hundred two thousand, six hundred eighty-nine".