78020990 has 16 divisors (see below), whose sum is σ = 148699152. Its totient is φ = 29372544.

The previous prime is 78020981. The next prime is 78021043. The reversal of 78020990 is 9902087.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 78020990.

It is a congruent number.

It is an unprimeable number.

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, 229304 + ... + 229643.

It is an arithmetic number, because the mean of its divisors is an integer number (9293697).

Almost surely, 2^78020990 is an apocalyptic number.

78020990 is a deficient number, since it is larger than the sum of its proper divisors (70678162).

78020990 is a wasteful number, since it uses less digits than its factorization.

78020990 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 458971.

The product of its (nonzero) digits is 9072, while the sum is 35.

The square root of 78020990 is about 8832.9491111406. The cubic root of 78020990 is about 427.3041908460.

The spelling of 78020990 in words is "seventy-eight million, twenty thousand, nine hundred ninety".