621612305 has 4 divisors (see below), whose sum is σ = 745934772. Its totient is φ = 497289840.

The previous prime is 621612287. The next prime is 621612307. The reversal of 621612305 is 503216126.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 353176849 + 268435456 = 18793^2 + 16384^2 .

It is not a de Polignac number, because 621612305 - 2¹² = 621608209 is a prime.

It is a super-4 number, since 4×621612305⁴ (a number of 36 digits) contains 4444 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (621612307) 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 3 ways as a sum of consecutive naturals, for example, 62161226 + ... + 62161235.

It is an arithmetic number, because the mean of its divisors is an integer number (186483693).

Almost surely, 2^621612305 is an apocalyptic number.

It is an amenable number.

621612305 is a deficient number, since it is larger than the sum of its proper divisors (124322467).

621612305 is a wasteful number, since it uses less digits than its factorization.

621612305 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 124322466.

The product of its (nonzero) digits is 2160, while the sum is 26.

The square root of 621612305 is about 24932.1540385102. The cubic root of 621612305 is about 853.4404066726.

The spelling of 621612305 in words is "six hundred twenty-one million, six hundred twelve thousand, three hundred five".