1278409423 has 2 divisors, whose sum is σ = 1278409424. Its totient is φ = 1278409422.

The previous prime is 1278409399. The next prime is 1278409427. The reversal of 1278409423 is 3249048721.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 1278409423 - 2²⁵ = 1244854991 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1278409427) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 639204711 + 639204712.

It is an arithmetic number, because the mean of its divisors is an integer number (639204712).

Almost surely, 2^1278409423 is an apocalyptic number.

1278409423 is a deficient number, since it is larger than the sum of its proper divisors (1).

1278409423 is an equidigital number, since it uses as much as digits as its factorization.

1278409423 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 96768, while the sum is 40.

The square root of 1278409423 is about 35754.8517407079. The cubic root of 1278409423 is about 1085.3171216562.

The spelling of 1278409423 in words is "one billion, two hundred seventy-eight million, four hundred nine thousand, four hundred twenty-three".