645136013 has 8 divisors (see below), whose sum is σ = 681801120. Its totient is φ = 608742000.

The previous prime is 645135983. The next prime is 645136021. The reversal of 645136013 is 310631546.

It is a happy number.

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 645136013 - 2⁶ = 645135949 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 (645136073) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 62870 + ... + 72407.

It is an arithmetic number, because the mean of its divisors is an integer number (85225140).

Almost surely, 2^645136013 is an apocalyptic number.

It is an amenable number.

645136013 is a deficient number, since it is larger than the sum of its proper divisors (36665107).

645136013 is a wasteful number, since it uses less digits than its factorization.

645136013 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 135547.

The product of its (nonzero) digits is 6480, while the sum is 29.

The square root of 645136013 is about 25399.5278105716. The cubic root of 645136013 is about 864.0729877505.

Adding to 645136013 its reverse (310631546), we get a palindrome (955767559).

The spelling of 645136013 in words is "six hundred forty-five million, one hundred thirty-six thousand, thirteen".