20540138231 has 2 divisors, whose sum is σ = 20540138232. Its totient is φ = 20540138230.

The previous prime is 20540138207. The next prime is 20540138237. The reversal of 20540138231 is 13283104502.

It is a happy number.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 20540138231 - 2³⁰ = 19466396407 is a prime.

It is a super-2 number, since 2×20540138231² (a number of 21 digits) contains 22 as substring.

It is a Sophie Germain prime.

It is a junction number, because it is equal to n+sod(n) for n = 20540138194 and 20540138203.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20540138237) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10270069115 + 10270069116.

It is an arithmetic number, because the mean of its divisors is an integer number (10270069116).

Almost surely, 2^20540138231 is an apocalyptic number.

20540138231 is a deficient number, since it is larger than the sum of its proper divisors (1).

20540138231 is an equidigital number, since it uses as much as digits as its factorization.

20540138231 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 5760, while the sum is 29.

The spelling of 20540138231 in words is "twenty billion, five hundred forty million, one hundred thirty-eight thousand, two hundred thirty-one".