77552820 has 144 divisors (see below), whose sum is σ = 245306880. Its totient is φ = 19819008.

The previous prime is 77552809. The next prime is 77552857. The reversal of 77552820 is 2825577.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 752889 + ... + 752991.

It is an arithmetic number, because the mean of its divisors is an integer number (1703520).

Almost surely, 2^77552820 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 77552820, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (122653440).

77552820 is an abundant number, since it is smaller than the sum of its proper divisors (167754060).

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

77552820 is a wasteful number, since it uses less digits than its factorization.

77552820 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 254 (or 249 counting only the distinct ones).

The product of its (nonzero) digits is 39200, while the sum is 36.

The square root of 77552820 is about 8806.4078942552. The cubic root of 77552820 is about 426.4477867682.

The spelling of 77552820 in words is "seventy-seven million, five hundred fifty-two thousand, eight hundred twenty".