78490039 has 2 divisors, whose sum is σ = 78490040. Its totient is φ = 78490038.

The previous prime is 78490021. The next prime is 78490043. The reversal of 78490039 is 93009487.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 78490039 - 2⁷ = 78489911 is a prime.

It is equal to p_4586386 and since 78490039 and 4586386 have the same sum of digits, it is a Honaker prime.

It is a junction number, because it is equal to n+sod(n) for n = 78489983 and 78490010.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (78490339) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 39245019 + 39245020.

It is an arithmetic number, because the mean of its divisors is an integer number (39245020).

Almost surely, 2^78490039 is an apocalyptic number.

78490039 is a deficient number, since it is larger than the sum of its proper divisors (1).

78490039 is an equidigital number, since it uses as much as digits as its factorization.

78490039 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 54432, while the sum is 40.

The square root of 78490039 is about 8859.4604237504. The cubic root of 78490039 is about 428.1587741058.

The spelling of 78490039 in words is "seventy-eight million, four hundred ninety thousand, thirty-nine".