645402735 has 40 divisors (see below), whose sum is σ = 1217850480. Its totient is φ = 326094336.

The previous prime is 645402727. The next prime is 645402749. The reversal of 645402735 is 537204546.

645402735 is a `hidden beast` number, since 64 + 540 + 27 + 35 = 666.

It is not a de Polignac number, because 645402735 - 2³ = 645402727 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 645402735.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 39 ways as a sum of consecutive naturals, for example, 34242 + ... + 49631.

It is an arithmetic number, because the mean of its divisors is an integer number (30446262).

Almost surely, 2^645402735 is an apocalyptic number.

645402735 is a deficient number, since it is larger than the sum of its proper divisors (572447745).

645402735 is a wasteful number, since it uses less digits than its factorization.

645402735 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 83909 (or 83900 counting only the distinct ones).

The product of its (nonzero) digits is 100800, while the sum is 36.

The square root of 645402735 is about 25404.7777986740. Note that the first 4 decimals coincide. The cubic root of 645402735 is about 864.1920507683.

The spelling of 645402735 in words is "six hundred forty-five million, four hundred two thousand, seven hundred thirty-five".