125987656891 has 16 divisors (see below), whose sum is σ = 128257668000. Its totient is φ = 123736504320.

The previous prime is 125987656889. The next prime is 125987656957. The reversal of 125987656891 is 198656789521.

It is a cyclic number.

It is not a de Polignac number, because 125987656891 - 2¹ = 125987656889 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (125987656391) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 44034801 + ... + 44037661.

It is an arithmetic number, because the mean of its divisors is an integer number (8016104250).

Almost surely, 2^125987656891 is an apocalyptic number.

125987656891 is a deficient number, since it is larger than the sum of its proper divisors (2270011109).

125987656891 is a wasteful number, since it uses less digits than its factorization.

125987656891 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5886.

The product of its digits is 65318400, while the sum is 67.

The spelling of 125987656891 in words is "one hundred twenty-five billion, nine hundred eighty-seven million, six hundred fifty-six thousand, eight hundred ninety-one".