644364470601 has 10 divisors (see below), whose sum is σ = 962569147562. Its totient is φ = 429576313680.

The previous prime is 644364470599. The next prime is 644364470609. The reversal of 644364470601 is 106074463446.

644364470601 is a `hidden beast` number, since 6 + 4 + 4 + 36 + 4 + 4 + 7 + 0 + 601 = 666.

It can be written as a sum of positive squares in only one way, i.e., 639238626576 + 5125844025 = 799524^2 + 71595^2 .

It is not a de Polignac number, because 644364470601 - 2¹ = 644364470599 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (644364470609) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 9 ways as a sum of consecutive naturals, for example, 3977558380 + ... + 3977558541.

Almost surely, 2^644364470601 is an apocalyptic number.

It is an amenable number.

644364470601 is a deficient number, since it is larger than the sum of its proper divisors (318204676961).

644364470601 is an equidigital number, since it uses as much as digits as its factorization.

644364470601 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7955116933 (or 7955116924 counting only the distinct ones).

The product of its (nonzero) digits is 1161216, while the sum is 45.

It can be divided in two parts, 6443644 and 70601, that added together give a triangular number (6514245 = T₃₆₀₉).

The spelling of 644364470601 in words is "six hundred forty-four billion, three hundred sixty-four million, four hundred seventy thousand, six hundred one".