756840121 has 2 divisors, whose sum is σ = 756840122. Its totient is φ = 756840120.

The previous prime is 756840113. The next prime is 756840137. The reversal of 756840121 is 121048657.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 705646096 + 51194025 = 26564^2 + 7155^2 .

It is a cyclic number.

It is not a de Polignac number, because 756840121 - 2³ = 756840113 is a prime.

It is not a weakly prime, because it can be changed into another prime (756840101) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 378420060 + 378420061.

It is an arithmetic number, because the mean of its divisors is an integer number (378420061).

Almost surely, 2^756840121 is an apocalyptic number.

It is an amenable number.

756840121 is a deficient number, since it is larger than the sum of its proper divisors (1).

756840121 is an equidigital number, since it uses as much as digits as its factorization.

756840121 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 13440, while the sum is 34.

The square root of 756840121 is about 27510.7273804238. The cubic root of 756840121 is about 911.3140140174.

Adding to 756840121 its reverse (121048657), we get a palindrome (877888778).

The spelling of 756840121 in words is "seven hundred fifty-six million, eight hundred forty thousand, one hundred twenty-one".