78302820 has 24 divisors (see below), whose sum is σ = 219248064. Its totient is φ = 20880736.

The previous prime is 78302803. The next prime is 78302827. The reversal of 78302820 is 2820387.

It is a super-2 number, since 2×78302820² = 12262663239904800, which contains 22 as substring.

It is a hoax number, since the sum of its digits (30) coincides with the sum of the digits of its distinct prime factors.

It is a Harshad number since it is a multiple of its sum of digits (30).

It is not an unprimeable number, because it can be changed into a prime (78302827) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 652464 + ... + 652583.

It is an arithmetic number, because the mean of its divisors is an integer number (9135336).

Almost surely, 2^78302820 is an apocalyptic number.

It is an amenable number.

78302820 is an abundant number, since it is smaller than the sum of its proper divisors (140945244).

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

78302820 is a wasteful number, since it uses less digits than its factorization.

78302820 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1305059 (or 1305057 counting only the distinct ones).

The product of its (nonzero) digits is 5376, while the sum is 30.

The square root of 78302820 is about 8848.8880657402. Note that the first 3 decimals coincide. The cubic root of 78302820 is about 427.8180800219.

The spelling of 78302820 in words is "seventy-eight million, three hundred two thousand, eight hundred twenty".