20451123571 has 2 divisors, whose sum is σ = 20451123572. Its totient is φ = 20451123570.

The previous prime is 20451123559. The next prime is 20451123619. The reversal of 20451123571 is 17532115402.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 20451123571 - 2⁷ = 20451123443 is a prime.

It is not a weakly prime, because it can be changed into another prime (20451123971) 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, 10225561785 + 10225561786.

It is an arithmetic number, because the mean of its divisors is an integer number (10225561786).

Almost surely, 2^20451123571 is an apocalyptic number.

20451123571 is a deficient number, since it is larger than the sum of its proper divisors (1).

20451123571 is an equidigital number, since it uses as much as digits as its factorization.

20451123571 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 8400, while the sum is 31.

Adding to 20451123571 its reverse (17532115402), we get a palindrome (37983238973).

The spelling of 20451123571 in words is "twenty billion, four hundred fifty-one million, one hundred twenty-three thousand, five hundred seventy-one".