78170849 has 2 divisors, whose sum is σ = 78170850. Its totient is φ = 78170848.

The previous prime is 78170837. The next prime is 78170867. The reversal of 78170849 is 94807187.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 70442449 + 7728400 = 8393^2 + 2780^2 .

It is an emirp because it is prime and its reverse (94807187) is a distict prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-78170849 is a prime.

It is a super-2 number, since 2×78170849² = 12221363266761602, which contains 22 as substring.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (78170749) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 39085424 + 39085425.

It is an arithmetic number, because the mean of its divisors is an integer number (39085425).

Almost surely, 2^78170849 is an apocalyptic number.

It is an amenable number.

78170849 is a deficient number, since it is larger than the sum of its proper divisors (1).

78170849 is an equidigital number, since it uses as much as digits as its factorization.

78170849 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 112896, while the sum is 44.

The square root of 78170849 is about 8841.4279955220. The cubic root of 78170849 is about 427.5775977148.

The spelling of 78170849 in words is "seventy-eight million, one hundred seventy thousand, eight hundred forty-nine".