645225871 has 8 divisors (see below), whose sum is σ = 685906704. Its totient is φ = 604848000.

The previous prime is 645225851. The next prime is 645225937. The reversal of 645225871 is 178522546.

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 645225871 - 2⁵ = 645225839 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (645225851) 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, 71340 + ... + 79873.

It is an arithmetic number, because the mean of its divisors is an integer number (85738338).

Almost surely, 2^645225871 is an apocalyptic number.

645225871 is a deficient number, since it is larger than the sum of its proper divisors (40680833).

645225871 is a wasteful number, since it uses less digits than its factorization.

645225871 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 151481.

The product of its digits is 134400, while the sum is 40.

The square root of 645225871 is about 25401.2966401324. The cubic root of 645225871 is about 864.1131034597.

It can be divided in two parts, 6452 and 25871, that added together give a palindrome (32323).

The spelling of 645225871 in words is "six hundred forty-five million, two hundred twenty-five thousand, eight hundred seventy-one".