125737242721 has 2 divisors, whose sum is σ = 125737242722. Its totient is φ = 125737242720.

The previous prime is 125737242667. The next prime is 125737242781. The reversal of 125737242721 is 127242737521.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 123685152721 + 2052090000 = 351689^2 + 45300^2 .

It is a cyclic number.

It is not a de Polignac number, because 125737242721 - 2²⁹ = 125200371809 is a prime.

It is not a weakly prime, because it can be changed into another prime (125737242781) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 62868621360 + 62868621361.

It is an arithmetic number, because the mean of its divisors is an integer number (62868621361).

Almost surely, 2^125737242721 is an apocalyptic number.

It is an amenable number.

125737242721 is a deficient number, since it is larger than the sum of its proper divisors (1).

125737242721 is an equidigital number, since it uses as much as digits as its factorization.

125737242721 is an evil number, because the sum of its binary digits is even.

The product of its digits is 329280, while the sum is 43.

The spelling of 125737242721 in words is "one hundred twenty-five billion, seven hundred thirty-seven million, two hundred forty-two thousand, seven hundred twenty-one".