621340809 has 16 divisors (see below), whose sum is σ = 841549824. Its totient is φ = 407699600.

The previous prime is 621340807. The next prime is 621340817. The reversal of 621340809 is 908043126.

It is a cyclic number.

It is not a de Polignac number, because 621340809 - 2¹ = 621340807 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 621340809.

It is not an unprimeable number, because it can be changed into a prime (621340801) 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, 143344 + ... + 147614.

It is an arithmetic number, because the mean of its divisors is an integer number (52596864).

Almost surely, 2^621340809 is an apocalyptic number.

It is an amenable number.

621340809 is a deficient number, since it is larger than the sum of its proper divisors (220209015).

621340809 is a wasteful number, since it uses less digits than its factorization.

621340809 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5028.

The product of its (nonzero) digits is 10368, while the sum is 33.

The square root of 621340809 is about 24926.7087478472. The cubic root of 621340809 is about 853.3161387560.

The spelling of 621340809 in words is "six hundred twenty-one million, three hundred forty thousand, eight hundred nine".