78345929 has 2 divisors, whose sum is σ = 78345930. Its totient is φ = 78345928.

The previous prime is 78345901. The next prime is 78345931. The reversal of 78345929 is 92954387.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 65934400 + 12411529 = 8120^2 + 3523^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-78345929 is a prime.

It is a super-2 number, since 2×78345929² = 12276169181746082, which contains 22 as substring.

Together with 78345931, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (78345989) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 39172964 + 39172965.

It is an arithmetic number, because the mean of its divisors is an integer number (39172965).

Almost surely, 2^78345929 is an apocalyptic number.

It is an amenable number.

78345929 is a deficient number, since it is larger than the sum of its proper divisors (1).

78345929 is an equidigital number, since it uses as much as digits as its factorization.

78345929 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 544320, while the sum is 47.

The square root of 78345929 is about 8851.3235733420. The cubic root of 78345929 is about 427.8965762418.

The spelling of 78345929 in words is "seventy-eight million, three hundred forty-five thousand, nine hundred twenty-nine".