125415109 has 2 divisors, whose sum is σ = 125415110. Its totient is φ = 125415108.

The previous prime is 125415071. The next prime is 125415193. The reversal of 125415109 is 901514521.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 90345025 + 35070084 = 9505^2 + 5922^2 .

It is an emirp because it is prime and its reverse (901514521) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 125415109 - 2¹³ = 125406917 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (125412109) 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, 62707554 + 62707555.

It is an arithmetic number, because the mean of its divisors is an integer number (62707555).

Almost surely, 2^125415109 is an apocalyptic number.

It is an amenable number.

125415109 is a deficient number, since it is larger than the sum of its proper divisors (1).

125415109 is an equidigital number, since it uses as much as digits as its factorization.

125415109 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1800, while the sum is 28.

The square root of 125415109 is about 11198.8887395134. Note that the first 3 decimals coincide. The cubic root of 125415109 is about 500.5528671172.

The spelling of 125415109 in words is "one hundred twenty-five million, four hundred fifteen thousand, one hundred nine".