645136755 has 16 divisors (see below), whose sum is σ = 1067813280. Its totient is φ = 332208128.

The previous prime is 645136733. The next prime is 645136781. The reversal of 645136755 is 557631546.

It is a cyclic number.

It is not a de Polignac number, because 645136755 - 2⁷ = 645136627 is a prime.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 741102 + ... + 741971.

It is an arithmetic number, because the mean of its divisors is an integer number (66738330).

Almost surely, 2^645136755 is an apocalyptic number.

645136755 is a deficient number, since it is larger than the sum of its proper divisors (422676525).

645136755 is a wasteful number, since it uses less digits than its factorization.

645136755 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1483110.

The product of its digits is 378000, while the sum is 42.

The square root of 645136755 is about 25399.5424171381. The cubic root of 645136755 is about 864.0733190202.

The spelling of 645136755 in words is "six hundred forty-five million, one hundred thirty-six thousand, seven hundred fifty-five".