644434362433416 has 64 divisors (see below), whose sum is σ = 1687830861265920. Its totient is φ = 204653212808000.

The previous prime is 644434362433321. The next prime is 644434362433417. The reversal of 644434362433416 is 614334263434446.

It is a nude number because it is divisible by every one of its digits.

It is not an unprimeable number, because it can be changed into a prime (644434362433417) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 2325466140 + ... + 2325743243.

It is an arithmetic number, because the mean of its divisors is an integer number (26372357207280).

Almost surely, 2^{644434362433416} is an apocalyptic number.

It is an amenable number.

644434362433416 is an abundant number, since it is smaller than the sum of its proper divisors (1043396498832504).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

644434362433416 is a wasteful number, since it uses less digits than its factorization.

644434362433416 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4651209666 (or 4651209662 counting only the distinct ones).

The product of its digits is 143327232, while the sum is 57.

The spelling of 644434362433416 in words is "six hundred forty-four trillion, four hundred thirty-four billion, three hundred sixty-two million, four hundred thirty-three thousand, four hundred sixteen".