1644352065 has 48 divisors (see below), whose sum is σ = 2955363840. Its totient is φ = 844888320.

The previous prime is 1644352037. The next prime is 1644352067. The reversal of 1644352065 is 5602534461.

1644352065 is a `hidden beast` number, since 1 + 6 + 443 + 5 + 206 + 5 = 666.

It is not a de Polignac number, because 1644352065 - 2¹⁸ = 1644089921 is a prime.

It is a super-3 number, since 3×1644352065³ (a number of 29 digits) contains 333 as substring.

It is not an unprimeable number, because it can be changed into a prime (1644352067) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 322506 + ... + 327564.

It is an arithmetic number, because the mean of its divisors is an integer number (61570080).

Almost surely, 2^1644352065 is an apocalyptic number.

1644352065 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

1644352065 is a deficient number, since it is larger than the sum of its proper divisors (1311011775).

1644352065 is a wasteful number, since it uses less digits than its factorization.

1644352065 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5334 (or 5331 counting only the distinct ones).

The product of its (nonzero) digits is 86400, while the sum is 36.

The square root of 1644352065 is about 40550.6111544573. The cubic root of 1644352065 is about 1180.3159321148.

The spelling of 1644352065 in words is "one billion, six hundred forty-four million, three hundred fifty-two thousand, sixty-five".