125966551 has 4 divisors (see below), whose sum is σ = 125989704. Its totient is φ = 125943400.

The previous prime is 125966483. The next prime is 125966579. The reversal of 125966551 is 155669521.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 125966551 - 2¹⁹ = 125442263 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (125964551) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1536 + ... + 15946.

It is an arithmetic number, because the mean of its divisors is an integer number (31497426).

Almost surely, 2^125966551 is an apocalyptic number.

125966551 is a deficient number, since it is larger than the sum of its proper divisors (23153).

125966551 is an equidigital number, since it uses as much as digits as its factorization.

125966551 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 23152.

The product of its digits is 81000, while the sum is 40.

The square root of 125966551 is about 11223.4821245458. The cubic root of 125966551 is about 501.2854271886.

The spelling of 125966551 in words is "one hundred twenty-five million, nine hundred sixty-six thousand, five hundred fifty-one".