125537981 has 2 divisors, whose sum is σ = 125537982. Its totient is φ = 125537980.

The previous prime is 125537977. The next prime is 125538041. The reversal of 125537981 is 189735521.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 124121881 + 1416100 = 11141^2 + 1190^2 .

It is a cyclic number.

It is not a de Polignac number, because 125537981 - 2² = 125537977 is a prime.

It is a super-2 number, since 2×125537981² = 31519569347112722, which contains 22 as substring.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (125537681) 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, 62768990 + 62768991.

It is an arithmetic number, because the mean of its divisors is an integer number (62768991).

Almost surely, 2^125537981 is an apocalyptic number.

It is an amenable number.

125537981 is a deficient number, since it is larger than the sum of its proper divisors (1).

125537981 is an equidigital number, since it uses as much as digits as its factorization.

125537981 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 75600, while the sum is 41.

The square root of 125537981 is about 11204.3732979583. The cubic root of 125537981 is about 500.7162813919.

The spelling of 125537981 in words is "one hundred twenty-five million, five hundred thirty-seven thousand, nine hundred eighty-one".