78315229 has 2 divisors, whose sum is σ = 78315230. Its totient is φ = 78315228.

The previous prime is 78315221. The next prime is 78315233. The reversal of 78315229 is 92251387.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 45562500 + 32752729 = 6750^2 + 5723^2 .

It is a cyclic number.

It is not a de Polignac number, because 78315229 - 2³ = 78315221 is a prime.

It is a super-2 number, since 2×78315229² = 12266550186644882, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (78315221) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 39157614 + 39157615.

It is an arithmetic number, because the mean of its divisors is an integer number (39157615).

Almost surely, 2^78315229 is an apocalyptic number.

It is an amenable number.

78315229 is a deficient number, since it is larger than the sum of its proper divisors (1).

78315229 is an equidigital number, since it uses as much as digits as its factorization.

78315229 is an evil number, because the sum of its binary digits is even.

The product of its digits is 30240, while the sum is 37.

The square root of 78315229 is about 8849.5891995053. The cubic root of 78315229 is about 427.8406782465.

The spelling of 78315229 in words is "seventy-eight million, three hundred fifteen thousand, two hundred twenty-nine".