126825617521 has 4 divisors (see below), whose sum is σ = 128133098212. Its totient is φ = 125518136832.

The previous prime is 126825617491. The next prime is 126825617603. The reversal of 126825617521 is 125716528621.

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 18643171600 + 108182445921 = 136540^2 + 328911^2 .

It is a cyclic number.

It is not a de Polignac number, because 126825617521 - 2³¹ = 124678133873 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (126825617921) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 653740200 + ... + 653740393.

It is an arithmetic number, because the mean of its divisors is an integer number (32033274553).

Almost surely, 2^126825617521 is an apocalyptic number.

It is an amenable number.

126825617521 is a deficient number, since it is larger than the sum of its proper divisors (1307480691).

126825617521 is an equidigital number, since it uses as much as digits as its factorization.

126825617521 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1307480690.

The product of its digits is 403200, while the sum is 46.

The spelling of 126825617521 in words is "one hundred twenty-six billion, eight hundred twenty-five million, six hundred seventeen thousand, five hundred twenty-one".