20109124957 has 2 divisors, whose sum is σ = 20109124958. Its totient is φ = 20109124956.

The previous prime is 20109124949. The next prime is 20109125021. The reversal of 20109124957 is 75942190102.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 16411147236 + 3697977721 = 128106^2 + 60811^2 .

It is a cyclic number.

It is not a de Polignac number, because 20109124957 - 2³ = 20109124949 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20109124907) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10054562478 + 10054562479.

It is an arithmetic number, because the mean of its divisors is an integer number (10054562479).

Almost surely, 2^20109124957 is an apocalyptic number.

It is an amenable number.

20109124957 is a deficient number, since it is larger than the sum of its proper divisors (1).

20109124957 is an equidigital number, since it uses as much as digits as its factorization.

20109124957 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 45360, while the sum is 40.

The spelling of 20109124957 in words is "twenty billion, one hundred nine million, one hundred twenty-four thousand, nine hundred fifty-seven".