621563491 has 8 divisors (see below), whose sum is σ = 628284384. Its totient is φ = 614856000.

The previous prime is 621563443. The next prime is 621563513. The reversal of 621563491 is 194365126.

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 621563491 - 2¹¹ = 621561443 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 621563491.

It is not an unprimeable number, because it can be changed into a prime (621563291) 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 7 ways as a sum of consecutive naturals, for example, 110241 + ... + 115741.

It is an arithmetic number, because the mean of its divisors is an integer number (78535548).

Almost surely, 2^621563491 is an apocalyptic number.

621563491 is a deficient number, since it is larger than the sum of its proper divisors (6720893).

621563491 is a wasteful number, since it uses less digits than its factorization.

621563491 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6701.

The product of its digits is 38880, while the sum is 37.

The square root of 621563491 is about 24931.1750826149. The cubic root of 621563491 is about 853.4180664185.

The spelling of 621563491 in words is "six hundred twenty-one million, five hundred sixty-three thousand, four hundred ninety-one".