645136726 has 16 divisors (see below), whose sum is σ = 1078081200. Its totient is φ = 287487648.

The previous prime is 645136721. The next prime is 645136727. The reversal of 645136726 is 627631546.

It is a super-3 number, since 3×645136726³ (a number of 27 digits) contains 333 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (645136721) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 427056 + ... + 428563.

It is an arithmetic number, because the mean of its divisors is an integer number (67380075).

Almost surely, 2^645136726 is an apocalyptic number.

645136726 is a deficient number, since it is larger than the sum of its proper divisors (432944474).

645136726 is a wasteful number, since it uses less digits than its factorization.

645136726 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 855663.

The product of its digits is 181440, while the sum is 40.

The square root of 645136726 is about 25399.5418462617. The cubic root of 645136726 is about 864.0733060730.

The spelling of 645136726 in words is "six hundred forty-five million, one hundred thirty-six thousand, seven hundred twenty-six".