645752247 has 8 divisors (see below), whose sum is σ = 984003456. Its totient is φ = 369001272.

The previous prime is 645752213. The next prime is 645752269. The reversal of 645752247 is 742257546.

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

It is not a de Polignac number, because 645752247 - 2¹² = 645748151 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 645752199 and 645752208.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (645752647) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 15375033 + ... + 15375074.

It is an arithmetic number, because the mean of its divisors is an integer number (123000432).

Almost surely, 2^645752247 is an apocalyptic number.

645752247 is a deficient number, since it is larger than the sum of its proper divisors (338251209).

645752247 is a wasteful number, since it uses less digits than its factorization.

645752247 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 30750117.

The product of its digits is 470400, while the sum is 42.

The square root of 645752247 is about 25411.6557311797. The cubic root of 645752247 is about 864.3480210737.

The spelling of 645752247 in words is "six hundred forty-five million, seven hundred fifty-two thousand, two hundred forty-seven".