645075955 has 4 divisors (see below), whose sum is σ = 774091152. Its totient is φ = 516060760.

The previous prime is 645075953. The next prime is 645075997. The reversal of 645075955 is 559570546.

It is a semiprime because it is the product of two primes.

It is not a de Polignac number, because 645075955 - 2¹ = 645075953 is a prime.

It is a super-2 number, since 2×645075955² = 832245975438324050, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (645075953) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 64507591 + ... + 64507600.

It is an arithmetic number, because the mean of its divisors is an integer number (193522788).

Almost surely, 2^645075955 is an apocalyptic number.

645075955 is a deficient number, since it is larger than the sum of its proper divisors (129015197).

645075955 is a wasteful number, since it uses less digits than its factorization.

645075955 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 129015196.

The product of its (nonzero) digits is 945000, while the sum is 46.

The square root of 645075955 is about 25398.3455169820. The cubic root of 645075955 is about 864.0461737119.

The spelling of 645075955 in words is "six hundred forty-five million, seventy-five thousand, nine hundred fifty-five".