645406085 has 8 divisors (see below), whose sum is σ = 774627576. Its totient is φ = 516231360.

The previous prime is 645406061. The next prime is 645406123. The reversal of 645406085 is 580604546.

It can be written as a sum of positive squares in 4 ways, for example, as 99062209 + 546343876 = 9953^2 + 23374^2 .

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

It is not a de Polignac number, because 645406085 - 2²⁶ = 578297221 is a prime.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 37487 + ... + 51923.

It is an arithmetic number, because the mean of its divisors is an integer number (96828447).

Almost surely, 2^645406085 is an apocalyptic number.

It is an amenable number.

645406085 is a deficient number, since it is larger than the sum of its proper divisors (129221491).

645406085 is a wasteful number, since it uses less digits than its factorization.

645406085 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 23383.

The product of its (nonzero) digits is 115200, while the sum is 38.

The square root of 645406085 is about 25404.8437310683. The cubic root of 645406085 is about 864.1935459785.

The spelling of 645406085 in words is "six hundred forty-five million, four hundred six thousand, eighty-five".