644412426615 has 12 divisors (see below), whose sum is σ = 1116981539544. Its totient is φ = 343686627504.

The previous prime is 644412426569. The next prime is 644412426641. The reversal of 644412426615 is 516624214446.

644412426615 is a `hidden beast` number, since 6 + 4 + 4 + 4 + 1 + 2 + 4 + 26 + 615 = 666.

It is not a de Polignac number, because 644412426615 - 2⁷ = 644412426487 is a prime.

It is a hoax number, since the sum of its digits (45) coincides with the sum of the digits of its distinct prime factors.

It is a Harshad number since it is a multiple of its sum of digits (45), and also a Moran number because the ratio is a prime number: 14320276147 = 644412426615 / (6 + 4 + 4 + 4 + 1 + 2 + 4 + 2 + 6 + 6 + 1 + 5).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 7160138029 + ... + 7160138118.

It is an arithmetic number, because the mean of its divisors is an integer number (93081794962).

Almost surely, 2^644412426615 is an apocalyptic number.

644412426615 is a deficient number, since it is larger than the sum of its proper divisors (472569112929).

644412426615 is a wasteful number, since it uses less digits than its factorization.

644412426615 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 14320276158 (or 14320276155 counting only the distinct ones).

The product of its digits is 1105920, while the sum is 45.

The spelling of 644412426615 in words is "six hundred forty-four billion, four hundred twelve million, four hundred twenty-six thousand, six hundred fifteen".