123078421 has 2 divisors, whose sum is σ = 123078422. Its totient is φ = 123078420.

The previous prime is 123078413. The next prime is 123078457. The reversal of 123078421 is 124870321.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 75881521 + 47196900 = 8711^2 + 6870^2 .

It is a cyclic number.

It is not a de Polignac number, because 123078421 - 2³ = 123078413 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 123078421.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (120078421) 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 as a sum of consecutive naturals, namely, 61539210 + 61539211.

It is an arithmetic number, because the mean of its divisors is an integer number (61539211).

Almost surely, 2^123078421 is an apocalyptic number.

It is an amenable number.

123078421 is a deficient number, since it is larger than the sum of its proper divisors (1).

123078421 is an equidigital number, since it uses as much as digits as its factorization.

123078421 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 2688, while the sum is 28.

The square root of 123078421 is about 11094.0714347799. The cubic root of 123078421 is about 497.4246526127.

The spelling of 123078421 in words is "one hundred twenty-three million, seventy-eight thousand, four hundred twenty-one".