77804020 has 24 divisors (see below), whose sum is σ = 186729984. Its totient is φ = 26675616.

The previous prime is 77804011. The next prime is 77804029. The reversal of 77804020 is 2040877.

It is an interprime number because it is at equal distance from previous prime (77804011) and next prime (77804029).

It is a Harshad number since it is a multiple of its sum of digits (28).

It is a self number, because there is not a number n which added to its sum of digits gives 77804020.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (77804029) 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, 277732 + ... + 278011.

It is an arithmetic number, because the mean of its divisors is an integer number (7780416).

Almost surely, 2^77804020 is an apocalyptic number.

77804020 is a gapful number since it is divisible by the number (70) formed by its first and last digit.

It is an amenable number.

77804020 is an abundant number, since it is smaller than the sum of its proper divisors (108925964).

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

77804020 is a wasteful number, since it uses less digits than its factorization.

77804020 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 555759 (or 555757 counting only the distinct ones).

The product of its (nonzero) digits is 3136, while the sum is 28.

The square root of 77804020 is about 8820.6587055616. The cubic root of 77804020 is about 426.9077237543.

Adding to 77804020 its reverse (2040877), we get a palindrome (79844897).

The spelling of 77804020 in words is "seventy-seven million, eight hundred four thousand, twenty".