125439551 has 4 divisors (see below), whose sum is σ = 126427392. Its totient is φ = 124451712.

The previous prime is 125439521. The next prime is 125439563. The reversal of 125439551 is 155934521.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-125439551 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 (125439521) 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 in 3 ways as a sum of consecutive naturals, for example, 493730 + ... + 493983.

It is an arithmetic number, because the mean of its divisors is an integer number (31606848).

Almost surely, 2^125439551 is an apocalyptic number.

125439551 is a deficient number, since it is larger than the sum of its proper divisors (987841).

125439551 is an equidigital number, since it uses as much as digits as its factorization.

125439551 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 987840.

The product of its digits is 27000, while the sum is 35.

The square root of 125439551 is about 11199.9799553392. The cubic root of 125439551 is about 500.5853823875.

The spelling of 125439551 in words is "one hundred twenty-five million, four hundred thirty-nine thousand, five hundred fifty-one".