42123149 has 2 divisors, whose sum is σ = 42123150. Its totient is φ = 42123148.

The previous prime is 42123121. The next prime is 42123157. The reversal of 42123149 is 94132124.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 40386025 + 1737124 = 6355^2 + 1318^2 .

It is a cyclic number.

It is not a de Polignac number, because 42123149 - 2²⁴ = 25345933 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (42123119) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 21061574 + 21061575.

It is an arithmetic number, because the mean of its divisors is an integer number (21061575).

Almost surely, 2^42123149 is an apocalyptic number.

It is an amenable number.

42123149 is a deficient number, since it is larger than the sum of its proper divisors (1).

42123149 is an equidigital number, since it uses as much as digits as its factorization.

42123149 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1728, while the sum is 26.

The square root of 42123149 is about 6490.2348955951. The cubic root of 42123149 is about 347.9420704428.

The spelling of 42123149 in words is "forty-two million, one hundred twenty-three thousand, one hundred forty-nine".