42278399 has 2 divisors, whose sum is σ = 42278400. Its totient is φ = 42278398.

The previous prime is 42278359. The next prime is 42278413. The reversal of 42278399 is 99387224.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-42278399 is a prime.

It is a super-3 number, since 3×42278399³ (a number of 24 digits) contains 333 as substring.

It is a zygodrome in base 3.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (42278329) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 21139199 + 21139200.

It is an arithmetic number, because the mean of its divisors is an integer number (21139200).

Almost surely, 2^42278399 is an apocalyptic number.

42278399 is a deficient number, since it is larger than the sum of its proper divisors (1).

42278399 is an equidigital number, since it uses as much as digits as its factorization.

42278399 is an evil number, because the sum of its binary digits is even.

The product of its digits is 217728, while the sum is 44.

The square root of 42278399 is about 6502.1841714919. The cubic root of 42278399 is about 348.3690073326.

The spelling of 42278399 in words is "forty-two million, two hundred seventy-eight thousand, three hundred ninety-nine".