78780813 has 8 divisors (see below), whose sum is σ = 105084000. Its totient is φ = 52499088.

The previous prime is 78780787. The next prime is 78780851. The reversal of 78780813 is 31808787.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 78780813 - 2¹⁶ = 78715277 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (78780113) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 7863 + ... + 14811.

It is an arithmetic number, because the mean of its divisors is an integer number (13135500).

Almost surely, 2^78780813 is an apocalyptic number.

It is an amenable number.

78780813 is a deficient number, since it is larger than the sum of its proper divisors (26303187).

78780813 is a wasteful number, since it uses less digits than its factorization.

78780813 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10731.

The product of its (nonzero) digits is 75264, while the sum is 42.

The square root of 78780813 is about 8875.8556207275. The cubic root of 78780813 is about 428.6868411869.

The spelling of 78780813 in words is "seventy-eight million, seven hundred eighty thousand, eight hundred thirteen".