820910078 has 4 divisors (see below), whose sum is σ = 1231365120. Its totient is φ = 410455038.

The previous prime is 820910071. The next prime is 820910087. The reversal of 820910078 is 870019028.

It is a happy number.

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (820910071) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 205227518 + ... + 205227521.

It is an arithmetic number, because the mean of its divisors is an integer number (307841280).

Almost surely, 2^820910078 is an apocalyptic number.

820910078 is a deficient number, since it is larger than the sum of its proper divisors (410455042).

820910078 is a wasteful number, since it uses less digits than its factorization.

820910078 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 410455041.

The product of its (nonzero) digits is 8064, while the sum is 35.

The square root of 820910078 is about 28651.5283711009. The cubic root of 820910078 is about 936.3363042314.

The spelling of 820910078 in words is "eight hundred twenty million, nine hundred ten thousand, seventy-eight".