125278559561 has 4 divisors (see below), whose sum is σ = 132647886612. Its totient is φ = 117909232512.

The previous prime is 125278559537. The next prime is 125278559633. The reversal of 125278559561 is 165955872521.

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

It can be written as a sum of positive squares in 2 ways, for example, as 98812150336 + 26466409225 = 314344^2 + 162685^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-125278559561 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 125278559497 and 125278559506.

It is not an unprimeable number, because it can be changed into a prime (125278555561) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3684663500 + ... + 3684663533.

It is an arithmetic number, because the mean of its divisors is an integer number (33161971653).

Almost surely, 2^125278559561 is an apocalyptic number.

It is an amenable number.

125278559561 is a deficient number, since it is larger than the sum of its proper divisors (7369327051).

125278559561 is an equidigital number, since it uses as much as digits as its factorization.

125278559561 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7369327050.

The product of its digits is 7560000, while the sum is 56.

The spelling of 125278559561 in words is "one hundred twenty-five billion, two hundred seventy-eight million, five hundred fifty-nine thousand, five hundred sixty-one".