125557801997 has 2 divisors, whose sum is σ = 125557801998. Its totient is φ = 125557801996.

The previous prime is 125557801949. The next prime is 125557802021. The reversal of 125557801997 is 799108755521.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 81446881321 + 44110920676 = 285389^2 + 210026^2 .

It is a cyclic number.

It is not a de Polignac number, because 125557801997 - 2¹² = 125557797901 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (125557801097) 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, 62778900998 + 62778900999.

It is an arithmetic number, because the mean of its divisors is an integer number (62778900999).

Almost surely, 2^125557801997 is an apocalyptic number.

It is an amenable number.

125557801997 is a deficient number, since it is larger than the sum of its proper divisors (1).

125557801997 is an equidigital number, since it uses as much as digits as its factorization.

125557801997 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 7938000, while the sum is 59.

The spelling of 125557801997 in words is "one hundred twenty-five billion, five hundred fifty-seven million, eight hundred one thousand, nine hundred ninety-seven".