78226785 has 72 divisors (see below), whose sum is σ = 169926120. Its totient is φ = 32997888.

The previous prime is 78226777. The next prime is 78226787. The reversal of 78226785 is 58762287.

It can be written as a sum of positive squares in 4 ways, for example, as 13198689 + 65028096 = 3633^2 + 8064^2 .

It is not a de Polignac number, because 78226785 - 2³ = 78226777 is a prime.

It is a super-2 number, since 2×78226785² = 12238859782872450, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a self number, because there is not a number n which added to its sum of digits gives 78226785.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (78226787) by changing a digit.

It is a polite number, since it can be written in 71 ways as a sum of consecutive naturals, for example, 27301 + ... + 30029.

It is an arithmetic number, because the mean of its divisors is an integer number (2360085).

Almost surely, 2^78226785 is an apocalyptic number.

It is an amenable number.

78226785 is an abundant number, since it is smaller than the sum of its proper divisors (91699335).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

78226785 is a wasteful number, since it uses less digits than its factorization.

78226785 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2767 (or 2757 counting only the distinct ones).

The product of its digits is 376320, while the sum is 45.

The square root of 78226785 is about 8844.5907197563. The cubic root of 78226785 is about 427.6795593300.

The spelling of 78226785 in words is "seventy-eight million, two hundred twenty-six thousand, seven hundred eighty-five".