125271757921 has 2 divisors, whose sum is σ = 125271757922. Its totient is φ = 125271757920.

The previous prime is 125271757903. The next prime is 125271757927. The reversal of 125271757921 is 129757172521.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 122682067600 + 2589690321 = 350260^2 + 50889^2 .

It is a cyclic number.

It is not a de Polignac number, because 125271757921 - 2³³ = 116681823329 is a prime.

It is not a weakly prime, because it can be changed into another prime (125271757927) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 62635878960 + 62635878961.

It is an arithmetic number, because the mean of its divisors is an integer number (62635878961).

Almost surely, 2^125271757921 is an apocalyptic number.

It is an amenable number.

125271757921 is a deficient number, since it is larger than the sum of its proper divisors (1).

125271757921 is an equidigital number, since it uses as much as digits as its factorization.

125271757921 is an evil number, because the sum of its binary digits is even.

The product of its digits is 617400, while the sum is 49.

The spelling of 125271757921 in words is "one hundred twenty-five billion, two hundred seventy-one million, seven hundred fifty-seven thousand, nine hundred twenty-one".