78330997 has 4 divisors (see below), whose sum is σ = 79049740. Its totient is φ = 77612256.

The previous prime is 78330991. The next prime is 78331013. The reversal of 78330997 is 79903387.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 79903387 = 37 ⋅2159551.

It can be written as a sum of positive squares in 2 ways, for example, as 44702596 + 33628401 = 6686^2 + 5799^2 .

It is a cyclic number.

It is not a de Polignac number, because 78330997 - 2¹¹ = 78328949 is a prime.

It is a super-2 number, since 2×78330997² = 12271490182028018, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (78330991) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 359208 + ... + 359425.

It is an arithmetic number, because the mean of its divisors is an integer number (19762435).

Almost surely, 2^78330997 is an apocalyptic number.

It is an amenable number.

78330997 is a deficient number, since it is larger than the sum of its proper divisors (718743).

78330997 is a wasteful number, since it uses less digits than its factorization.

78330997 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 718742.

The product of its (nonzero) digits is 285768, while the sum is 46.

The square root of 78330997 is about 8850.4800434779. The cubic root of 78330997 is about 427.8693901552.

The spelling of 78330997 in words is "seventy-eight million, three hundred thirty thousand, nine hundred ninety-seven".