78213328 has 20 divisors (see below), whose sum is σ = 160452900. Its totient is φ = 36806144.

The previous prime is 78213313. The next prime is 78213337. The reversal of 78213328 is 82331287.

It can be written as a sum of positive squares in 2 ways, for example, as 45859984 + 32353344 = 6772^2 + 5688^2 .

It is a super-2 number, since 2×78213328² = 12234649353671168, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (34).

It is a junction number, because it is equal to n+sod(n) for n = 78213293 and 78213302.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 143503 + ... + 144046.

It is an arithmetic number, because the mean of its divisors is an integer number (8022645).

Almost surely, 2^78213328 is an apocalyptic number.

It is an amenable number.

78213328 is an abundant number, since it is smaller than the sum of its proper divisors (82239572).

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

78213328 is a wasteful number, since it uses less digits than its factorization.

78213328 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 287574 (or 287568 counting only the distinct ones).

The product of its digits is 16128, while the sum is 34.

The square root of 78213328 is about 8843.8299395680. The cubic root of 78213328 is about 427.6550339969.

The spelling of 78213328 in words is "seventy-eight million, two hundred thirteen thousand, three hundred twenty-eight".