125217551 has 2 divisors, whose sum is σ = 125217552. Its totient is φ = 125217550.

The previous prime is 125217539. The next prime is 125217553. The reversal of 125217551 is 155712521.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 125217551 - 2¹⁰ = 125216527 is a prime.

Together with 125217553, it forms a pair of twin primes.

It is a Chen prime.

It is equal to p_7121792 and since 125217551 and 7121792 have the same sum of digits, it is a Honaker prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (125217553) 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, 62608775 + 62608776.

It is an arithmetic number, because the mean of its divisors is an integer number (62608776).

Almost surely, 2^125217551 is an apocalyptic number.

125217551 is a deficient number, since it is larger than the sum of its proper divisors (1).

125217551 is an equidigital number, since it uses as much as digits as its factorization.

125217551 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 3500, while the sum is 29.

The square root of 125217551 is about 11190.0648344860. The cubic root of 125217551 is about 500.2898998836.

The spelling of 125217551 in words is "one hundred twenty-five million, two hundred seventeen thousand, five hundred fifty-one".