20517371123 has 2 divisors, whose sum is σ = 20517371124. Its totient is φ = 20517371122.

The previous prime is 20517371107. The next prime is 20517371131. The reversal of 20517371123 is 32117371502.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 20517371123 - 2⁴ = 20517371107 is a prime.

It is a super-2 number, since 2×20517371123² (a number of 21 digits) contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 20517371123.

It is not a weakly prime, because it can be changed into another prime (20517371143) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10258685561 + 10258685562.

It is an arithmetic number, because the mean of its divisors is an integer number (10258685562).

Almost surely, 2^20517371123 is an apocalyptic number.

20517371123 is a deficient number, since it is larger than the sum of its proper divisors (1).

20517371123 is an equidigital number, since it uses as much as digits as its factorization.

20517371123 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 8820, while the sum is 32.

The spelling of 20517371123 in words is "twenty billion, five hundred seventeen million, three hundred seventy-one thousand, one hundred twenty-three".