621381717 has 12 divisors (see below), whose sum is σ = 979147104. Its totient is φ = 376594920.

The previous prime is 621381659. The next prime is 621381727. The reversal of 621381717 is 717183126.

621381717 is a `hidden beast` number, since 621 + 3 + 8 + 17 + 17 = 666.

It is not a de Polignac number, because 621381717 - 2¹¹ = 621379669 is a prime.

It is a super-2 number, since 2×621381717² = 772230476443736178, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (621381727) 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 11 ways as a sum of consecutive naturals, for example, 3138193 + ... + 3138390.

It is an arithmetic number, because the mean of its divisors is an integer number (81595592).

Almost surely, 2^621381717 is an apocalyptic number.

It is an amenable number.

621381717 is a deficient number, since it is larger than the sum of its proper divisors (357765387).

621381717 is a wasteful number, since it uses less digits than its factorization.

621381717 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6276600 (or 6276597 counting only the distinct ones).

The product of its digits is 14112, while the sum is 36.

The square root of 621381717 is about 24927.5292999527. The cubic root of 621381717 is about 853.3348652961.

The spelling of 621381717 in words is "six hundred twenty-one million, three hundred eighty-one thousand, seven hundred seventeen".