125837821 has 4 divisors (see below), whose sum is σ = 125880700. Its totient is φ = 125794944.

The previous prime is 125837797. The next prime is 125837837. The reversal of 125837821 is 128738521.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 109725625 + 16112196 = 10475^2 + 4014^2 .

It is a cyclic number.

It is not a de Polignac number, because 125837821 - 2¹³ = 125829629 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (125837861) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 16686 + ... + 23023.

It is an arithmetic number, because the mean of its divisors is an integer number (31470175).

Almost surely, 2^125837821 is an apocalyptic number.

It is an amenable number.

125837821 is a deficient number, since it is larger than the sum of its proper divisors (42879).

125837821 is an equidigital number, since it uses as much as digits as its factorization.

125837821 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 42878.

The product of its digits is 26880, while the sum is 37.

The square root of 125837821 is about 11217.7458074249. The cubic root of 125837821 is about 501.1146081178.

The spelling of 125837821 in words is "one hundred twenty-five million, eight hundred thirty-seven thousand, eight hundred twenty-one".