125773721 has 2 divisors, whose sum is σ = 125773722. Its totient is φ = 125773720.

The previous prime is 125773709. The next prime is 125773723. The reversal of 125773721 is 127377521.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 107412496 + 18361225 = 10364^2 + 4285^2 .

It is an emirp because it is prime and its reverse (127377521) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 125773721 - 2⁶ = 125773657 is a prime.

Together with 125773723, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (125773723) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 62886860 + 62886861.

It is an arithmetic number, because the mean of its divisors is an integer number (62886861).

Almost surely, 2^125773721 is an apocalyptic number.

It is an amenable number.

125773721 is a deficient number, since it is larger than the sum of its proper divisors (1).

125773721 is an equidigital number, since it uses as much as digits as its factorization.

125773721 is an evil number, because the sum of its binary digits is even.

The product of its digits is 20580, while the sum is 35.

The square root of 125773721 is about 11214.8883632429. Note that the first 3 decimals coincide. The cubic root of 125773721 is about 501.0295067767.

The spelling of 125773721 in words is "one hundred twenty-five million, seven hundred seventy-three thousand, seven hundred twenty-one".