20602397909 has 2 divisors, whose sum is σ = 20602397910. Its totient is φ = 20602397908.

The previous prime is 20602397891. The next prime is 20602397941. The reversal of 20602397909 is 90979320602.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 18975889009 + 1626508900 = 137753^2 + 40330^2 .

It is a cyclic number.

It is not a de Polignac number, because 20602397909 - 2⁸ = 20602397653 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20602397209) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10301198954 + 10301198955.

It is an arithmetic number, because the mean of its divisors is an integer number (10301198955).

Almost surely, 2^20602397909 is an apocalyptic number.

It is an amenable number.

20602397909 is a deficient number, since it is larger than the sum of its proper divisors (1).

20602397909 is an equidigital number, since it uses as much as digits as its factorization.

20602397909 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 367416, while the sum is 47.

The spelling of 20602397909 in words is "twenty billion, six hundred two million, three hundred ninety-seven thousand, nine hundred nine".