644054453 has 8 divisors (see below), whose sum is σ = 736646208. Its totient is φ = 551608704.

The previous prime is 644054447. The next prime is 644054459. The reversal of 644054453 is 354450446.

It is an interprime number because it is at equal distance from previous prime (644054447) and next prime (644054459).

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 644054453 - 2¹⁸ = 643792309 is a prime.

It is a super-2 number, since 2×644054453² = 829612276858258418, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (644054459) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 26876 + ... + 44837.

It is an arithmetic number, because the mean of its divisors is an integer number (92080776).

Almost surely, 2^644054453 is an apocalyptic number.

It is an amenable number.

644054453 is a deficient number, since it is larger than the sum of its proper divisors (92591755).

644054453 is a wasteful number, since it uses less digits than its factorization.

644054453 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 73003.

The product of its (nonzero) digits is 115200, while the sum is 35.

The square root of 644054453 is about 25378.2279326197. The cubic root of 644054453 is about 863.5898495701.

The spelling of 644054453 in words is "six hundred forty-four million, fifty-four thousand, four hundred fifty-three".