645254066329 has 4 divisors (see below), whose sum is σ = 673308590976. Its totient is φ = 617199541684.

The previous prime is 645254066267. The next prime is 645254066411. The reversal of 645254066329 is 923660452546.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 645254066329 - 2⁷ = 645254066201 is a prime.

It is a super-2 number, since 2×645254066329² (a number of 24 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (645254066029) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 14027262289 + ... + 14027262334.

It is an arithmetic number, because the mean of its divisors is an integer number (168327147744).

Almost surely, 2^645254066329 is an apocalyptic number.

It is an amenable number.

645254066329 is a deficient number, since it is larger than the sum of its proper divisors (28054524647).

645254066329 is a wasteful number, since it uses less digits than its factorization.

645254066329 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 28054524646.

The product of its (nonzero) digits is 9331200, while the sum is 52.

The spelling of 645254066329 in words is "six hundred forty-five billion, two hundred fifty-four million, sixty-six thousand, three hundred twenty-nine".