620660 has 12 divisors (see below), whose sum is σ = 1303428. Its totient is φ = 248256.

The previous prime is 620657. The next prime is 620663. The reversal of 620660 is 66026.

620660 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is an interprime number because it is at equal distance from previous prime (620657) and next prime (620663).

It can be written as a sum of positive squares in 2 ways, for example, as 320356 + 300304 = 566^2 + 548^2 .

It is a Harshad number since it is a multiple of its sum of digits (20), and also a Moran number because the ratio is a prime number: 31033 = 620660 / (6 + 2 + 0 + 6 + 6 + 0).

It is an Ulam number.

It is a plaindrome in base 14.

It is a congruent number.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 620660.

It is not an unprimeable number, because it can be changed into a prime (620663) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 15497 + ... + 15536.

It is an arithmetic number, because the mean of its divisors is an integer number (108619).

2⁶²⁰⁶⁶⁰ is an apocalyptic number.

It is an amenable number.

620660 is an abundant number, since it is smaller than the sum of its proper divisors (682768).

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

620660 is a wasteful number, since it uses less digits than its factorization.

620660 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 31042 (or 31040 counting only the distinct ones).

The product of its (nonzero) digits is 432, while the sum is 20.

The square root of 620660 is about 787.8197763448. The cubic root of 620660 is about 85.3004362669.

Adding to 620660 its reverse (66026), we get a palindrome (686686).

The spelling of 620660 in words is "six hundred twenty thousand, six hundred sixty".