125561549 has 2 divisors, whose sum is σ = 125561550. Its totient is φ = 125561548.

The previous prime is 125561543. The next prime is 125561567. The reversal of 125561549 is 945165521.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 107226025 + 18335524 = 10355^2 + 4282^2 .

It is a cyclic number.

It is not a de Polignac number, because 125561549 - 2¹⁶ = 125496013 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (125561543) 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, 62780774 + 62780775.

It is an arithmetic number, because the mean of its divisors is an integer number (62780775).

Almost surely, 2^125561549 is an apocalyptic number.

It is an amenable number.

125561549 is a deficient number, since it is larger than the sum of its proper divisors (1).

125561549 is an equidigital number, since it uses as much as digits as its factorization.

125561549 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 54000, while the sum is 38.

The square root of 125561549 is about 11205.4249807850. The cubic root of 125561549 is about 500.7476135907.

The spelling of 125561549 in words is "one hundred twenty-five million, five hundred sixty-one thousand, five hundred forty-nine".