620665 has 4 divisors (see below), whose sum is σ = 744804. Its totient is φ = 496528.

The previous prime is 620663. The next prime is 620671. The reversal of 620665 is 566026.

620665 is nontrivially palindromic in base 16.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 251001 + 369664 = 501^2 + 608^2 .

It is a cyclic number.

It is not a de Polignac number, because 620665 - 2¹ = 620663 is a prime.

It is a Duffinian number.

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

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 62062 + ... + 62071.

It is an arithmetic number, because the mean of its divisors is an integer number (186201).

2⁶²⁰⁶⁶⁵ is an apocalyptic number.

It is an amenable number.

620665 is a deficient number, since it is larger than the sum of its proper divisors (124139).

620665 is a wasteful number, since it uses less digits than its factorization.

620665 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 124138.

The product of its (nonzero) digits is 2160, while the sum is 25.

The square root of 620665 is about 787.8229496530. The cubic root of 620665 is about 85.3006653247.

The spelling of 620665 in words is "six hundred twenty thousand, six hundred sixty-five".