78860069 has 2 divisors, whose sum is σ = 78860070. Its totient is φ = 78860068.

The previous prime is 78860017. The next prime is 78860087. The reversal of 78860069 is 96006887.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 64609444 + 14250625 = 8038^2 + 3775^2 .

It is a cyclic number.

It is not a de Polignac number, because 78860069 - 2²⁰ = 77811493 is a prime.

It is a super-2 number, since 2×78860069² = 12437820965369522, which contains 22 as substring.

It is a Sophie Germain prime.

It is a Curzon number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (78860009) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 39430034 + 39430035.

It is an arithmetic number, because the mean of its divisors is an integer number (39430035).

Almost surely, 2^78860069 is an apocalyptic number.

It is an amenable number.

78860069 is a deficient number, since it is larger than the sum of its proper divisors (1).

78860069 is an equidigital number, since it uses as much as digits as its factorization.

78860069 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 145152, while the sum is 44.

The square root of 78860069 is about 8880.3191947137. The cubic root of 78860069 is about 428.8305505315.

The spelling of 78860069 in words is "seventy-eight million, eight hundred sixty thousand, sixty-nine".