125440543121 has 2 divisors, whose sum is σ = 125440543122. Its totient is φ = 125440543120.

The previous prime is 125440543079. The next prime is 125440543133. The reversal of 125440543121 is 121345044521.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 105963270400 + 19477272721 = 325520^2 + 139561^2 .

It is a cyclic number.

It is not a de Polignac number, because 125440543121 - 2¹⁴ = 125440526737 is a prime.

It is not a weakly prime, because it can be changed into another prime (125440543141) 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, 62720271560 + 62720271561.

It is an arithmetic number, because the mean of its divisors is an integer number (62720271561).

Almost surely, 2^125440543121 is an apocalyptic number.

It is an amenable number.

125440543121 is a deficient number, since it is larger than the sum of its proper divisors (1).

125440543121 is an equidigital number, since it uses as much as digits as its factorization.

125440543121 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 19200, while the sum is 32.

Adding to 125440543121 its reverse (121345044521), we get a palindrome (246785587642).

The spelling of 125440543121 in words is "one hundred twenty-five billion, four hundred forty million, five hundred forty-three thousand, one hundred twenty-one".