20310999997 has 2 divisors, whose sum is σ = 20310999998. Its totient is φ = 20310999996.

The previous prime is 20310999979. The next prime is 20311000001. The reversal of 20310999997 is 79999901302.

Together with previous prime (20310999979) it forms an Ormiston pair, because they use the same digits, order apart.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 20148666916 + 162333081 = 141946^2 + 12741^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-20310999997 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20310999697) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10155499998 + 10155499999.

It is an arithmetic number, because the mean of its divisors is an integer number (10155499999).

Almost surely, 2^20310999997 is an apocalyptic number.

It is an amenable number.

20310999997 is a deficient number, since it is larger than the sum of its proper divisors (1).

20310999997 is an equidigital number, since it uses as much as digits as its factorization.

20310999997 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 2480058, while the sum is 58.

The spelling of 20310999997 in words is "twenty billion, three hundred ten million, nine hundred ninety-nine thousand, nine hundred ninety-seven".