126715306021 has 4 divisors (see below), whose sum is σ = 126716058700. Its totient is φ = 126714553344.

The previous prime is 126715305991. The next prime is 126715306049. The reversal of 126715306021 is 120603517621.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It can be written as a sum of positive squares in 2 ways, for example, as 57785428996 + 68929877025 = 240386^2 + 262545^2 .

It is a cyclic number.

It is not a de Polignac number, because 126715306021 - 2¹³ = 126715297829 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 (126715306051) 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, 4975 + ... + 503443.

It is an arithmetic number, because the mean of its divisors is an integer number (31679014675).

Almost surely, 2^126715306021 is an apocalyptic number.

It is an amenable number.

126715306021 is a deficient number, since it is larger than the sum of its proper divisors (752679).

126715306021 is an equidigital number, since it uses as much as digits as its factorization.

126715306021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 752678.

The product of its (nonzero) digits is 15120, while the sum is 34.

The spelling of 126715306021 in words is "one hundred twenty-six billion, seven hundred fifteen million, three hundred six thousand, twenty-one".