621669 has 8 divisors (see below), whose sum is σ = 846720. Its totient is φ = 405536.

The previous prime is 621641. The next prime is 621671. The reversal of 621669 is 966126.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 621669 - 2⁷ = 621541 is a prime.

It is a super-2 number, since 2×621669² = 772944691122, which contains 22 as substring.

621669 is a lucky number.

It is a plaindrome in base 14.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (621619) 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 7 ways as a sum of consecutive naturals, for example, 2064 + ... + 2345.

It is an arithmetic number, because the mean of its divisors is an integer number (105840).

2⁶²¹⁶⁶⁹ is an apocalyptic number.

It is an amenable number.

621669 is a deficient number, since it is larger than the sum of its proper divisors (225051).

621669 is a wasteful number, since it uses less digits than its factorization.

621669 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4459.

The product of its digits is 3888, while the sum is 30.

The square root of 621669 is about 788.4598911803. The cubic root of 621669 is about 85.3466352283.

The spelling of 621669 in words is "six hundred twenty-one thousand, six hundred sixty-nine".