78761965 has 4 divisors (see below), whose sum is σ = 94514364. Its totient is φ = 63009568.

The previous prime is 78761953. The next prime is 78761981. The reversal of 78761965 is 56916787.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 37429924 + 41332041 = 6118^2 + 6429^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-78761965 is a prime.

It is a super-2 number, since 2×78761965² = 12406894261322450, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 7876192 + ... + 7876201.

It is an arithmetic number, because the mean of its divisors is an integer number (23628591).

Almost surely, 2^78761965 is an apocalyptic number.

It is an amenable number.

78761965 is a deficient number, since it is larger than the sum of its proper divisors (15752399).

78761965 is a wasteful number, since it uses less digits than its factorization.

78761965 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 15752398.

The product of its digits is 635040, while the sum is 49.

The square root of 78761965 is about 8874.7938004215. The cubic root of 78761965 is about 428.6526512460.

The spelling of 78761965 in words is "seventy-eight million, seven hundred sixty-one thousand, nine hundred sixty-five".