621985 has 16 divisors (see below), whose sum is σ = 919296. Its totient is φ = 393408.

The previous prime is 621983. The next prime is 621997. The reversal of 621985 is 589126.

It is a cyclic number.

It is not a de Polignac number, because 621985 - 2¹ = 621983 is a prime.

It is not an unprimeable number, because it can be changed into a prime (621983) 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 15 ways as a sum of consecutive naturals, for example, 229 + ... + 1138.

It is an arithmetic number, because the mean of its divisors is an integer number (57456).

2⁶²¹⁹⁸⁵ is an apocalyptic number.

621985 is a gapful number since it is divisible by the number (65) formed by its first and last digit.

It is an amenable number.

621985 is a deficient number, since it is larger than the sum of its proper divisors (297311).

621985 is a wasteful number, since it uses less digits than its factorization.

621985 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1392.

The product of its digits is 4320, while the sum is 31.

The square root of 621985 is about 788.6602563842. The cubic root of 621985 is about 85.3610936022.

The spelling of 621985 in words is "six hundred twenty-one thousand, nine hundred eighty-five".