125724492721 has 2 divisors, whose sum is σ = 125724492722. Its totient is φ = 125724492720.

The previous prime is 125724492703. The next prime is 125724492791. The reversal of 125724492721 is 127294427521.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 122857961121 + 2866531600 = 350511^2 + 53540^2 .

It is a cyclic number.

It is not a de Polignac number, because 125724492721 - 2³⁵ = 91364754353 is a prime.

It is not a weakly prime, because it can be changed into another prime (125724492791) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 62862246360 + 62862246361.

It is an arithmetic number, because the mean of its divisors is an integer number (62862246361).

Almost surely, 2^125724492721 is an apocalyptic number.

It is an amenable number.

125724492721 is a deficient number, since it is larger than the sum of its proper divisors (1).

125724492721 is an equidigital number, since it uses as much as digits as its factorization.

125724492721 is an evil number, because the sum of its binary digits is even.

The product of its digits is 564480, while the sum is 46.

The spelling of 125724492721 in words is "one hundred twenty-five billion, seven hundred twenty-four million, four hundred ninety-two thousand, seven hundred twenty-one".