125854360821221 has 2 divisors, whose sum is σ = 125854360821222. Its totient is φ = 125854360821220.

The previous prime is 125854360821209. The next prime is 125854360821317. The reversal of 125854360821221 is 122128063458521.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 96159871780996 + 29694489040225 = 9806114^2 + 5449265^2 .

It is an emirp because it is prime and its reverse (122128063458521) is a distict prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-125854360821221 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 125854360821221.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (125854360823221) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 62927180410610 + 62927180410611.

It is an arithmetic number, because the mean of its divisors is an integer number (62927180410611).

Almost surely, 2^{125854360821221} is an apocalyptic number.

It is an amenable number.

125854360821221 is a deficient number, since it is larger than the sum of its proper divisors (1).

125854360821221 is an equidigital number, since it uses as much as digits as its factorization.

125854360821221 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1843200, while the sum is 50.

The spelling of 125854360821221 in words is "one hundred twenty-five trillion, eight hundred fifty-four billion, three hundred sixty million, eight hundred twenty-one thousand, two hundred twenty-one".