83720628 has 60 divisors (see below), whose sum is σ = 219999780. Its totient is φ = 27762048.

The previous prime is 83720599. The next prime is 83720629. The reversal of 83720628 is 82602738.

It is a happy number.

83720628 is a `hidden beast` number, since 8 + 3 + 7 + 20 + 628 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 7193124 + 76527504 = 2682^2 + 8748^2 .

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

It is a junction number, because it is equal to n+sod(n) for n = 83720592 and 83720601.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (83720629) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 19 ways as a sum of consecutive naturals, for example, 74938 + ... + 76046.

It is an arithmetic number, because the mean of its divisors is an integer number (3666663).

Almost surely, 2^83720628 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 83720628, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (109999890).

83720628 is an abundant number, since it is smaller than the sum of its proper divisors (136279152).

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

83720628 is a wasteful number, since it uses less digits than its factorization.

83720628 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1358 (or 1347 counting only the distinct ones).

The product of its (nonzero) digits is 32256, while the sum is 36.

The square root of 83720628 is about 9149.8977043462. The cubic root of 83720628 is about 437.4658528995.

It can be divided in two parts, 83720 and 628, that added together give a palindrome (84348).

The spelling of 83720628 in words is "eighty-three million, seven hundred twenty thousand, six hundred twenty-eight".