125826821 has 2 divisors, whose sum is σ = 125826822. Its totient is φ = 125826820.

The previous prime is 125826817. The next prime is 125826829. The reversal of 125826821 is 128628521.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 102921025 + 22905796 = 10145^2 + 4786^2 .

It is a cyclic number.

It is not a de Polignac number, because 125826821 - 2² = 125826817 is a prime.

It is a Sophie Germain prime.

It is a Curzon number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (125826829) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 62913410 + 62913411.

It is an arithmetic number, because the mean of its divisors is an integer number (62913411).

Almost surely, 2^125826821 is an apocalyptic number.

It is an amenable number.

125826821 is a deficient number, since it is larger than the sum of its proper divisors (1).

125826821 is an equidigital number, since it uses as much as digits as its factorization.

125826821 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 15360, while the sum is 35.

The square root of 125826821 is about 11217.2555021271. The cubic root of 125826821 is about 501.1000061980.

The spelling of 125826821 in words is "one hundred twenty-five million, eight hundred twenty-six thousand, eight hundred twenty-one".