125849021 has 2 divisors, whose sum is σ = 125849022. Its totient is φ = 125849020.

The previous prime is 125848973. The next prime is 125849041. The reversal of 125849021 is 120948521.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 118483225 + 7365796 = 10885^2 + 2714^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-125849021 is a prime.

It is a Sophie Germain prime.

It is a Chen prime.

It is a Curzon number.

It is equal to p_7155680 and since 125849021 and 7155680 have the same sum of digits, it is a Honaker prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (125849041) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 62924510 + 62924511.

It is an arithmetic number, because the mean of its divisors is an integer number (62924511).

Almost surely, 2^125849021 is an apocalyptic number.

It is an amenable number.

125849021 is a deficient number, since it is larger than the sum of its proper divisors (1).

125849021 is an equidigital number, since it uses as much as digits as its factorization.

125849021 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 5760, while the sum is 32.

The square root of 125849021 is about 11218.2450053473. The cubic root of 125849021 is about 501.1294746528.

The spelling of 125849021 in words is "one hundred twenty-five million, eight hundred forty-nine thousand, twenty-one".