645525547 has 8 divisors (see below), whose sum is σ = 685917936. Its totient is φ = 605402112.

The previous prime is 645525541. The next prime is 645525557. The reversal of 645525547 is 745525546.

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 645525547 - 2¹⁵ = 645492779 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (645525541) 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, 62278 + ... + 71899.

It is an arithmetic number, because the mean of its divisors is an integer number (85739742).

Almost surely, 2^645525547 is an apocalyptic number.

645525547 is a deficient number, since it is larger than the sum of its proper divisors (40392389).

645525547 is a wasteful number, since it uses less digits than its factorization.

645525547 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 134477.

The product of its digits is 840000, while the sum is 43.

The square root of 645525547 is about 25407.1947880910. The cubic root of 645525547 is about 864.2468622408.

Subtracting 645525547 from its reverse (745525546), we obtain a palindrome (99999999).

The spelling of 645525547 in words is "six hundred forty-five million, five hundred twenty-five thousand, five hundred forty-seven".