621291 has 16 divisors (see below), whose sum is σ = 920448. Its totient is φ = 369600.

The previous prime is 621289. The next prime is 621301. The reversal of 621291 is 192126.

It is not a de Polignac number, because 621291 - 2¹ = 621289 is a prime.

It is a plaindrome in base 14.

It is not an unprimeable number, because it can be changed into a prime (621241) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 2071 + ... + 2351.

It is an arithmetic number, because the mean of its divisors is an integer number (57528).

2⁶²¹²⁹¹ is an apocalyptic number.

621291 is a deficient number, since it is larger than the sum of its proper divisors (299157).

621291 is a wasteful number, since it uses less digits than its factorization.

621291 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 362.

The product of its digits is 216, while the sum is 21.

The square root of 621291 is about 788.2201469133. The cubic root of 621291 is about 85.3293336477.

The spelling of 621291 in words is "six hundred twenty-one thousand, two hundred ninety-one".