645753701 has 8 divisors (see below), whose sum is σ = 674638200. Its totient is φ = 617310400.

The previous prime is 645753697. The next prime is 645753707. The reversal of 645753701 is 107357546.

It can be written as a sum of positive squares in 4 ways, for example, as 80550625 + 565203076 = 8975^2 + 23774^2 .

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 645753701 - 2² = 645753697 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 (645753707) 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, 107306 + ... + 113163.

It is an arithmetic number, because the mean of its divisors is an integer number (84329775).

Almost surely, 2^645753701 is an apocalyptic number.

It is an amenable number.

645753701 is a deficient number, since it is larger than the sum of its proper divisors (28884499).

645753701 is a wasteful number, since it uses less digits than its factorization.

645753701 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 220599.

The product of its (nonzero) digits is 88200, while the sum is 38.

The square root of 645753701 is about 25411.6843400826. The cubic root of 645753701 is about 864.3486698060.

The spelling of 645753701 in words is "six hundred forty-five million, seven hundred fifty-three thousand, seven hundred one".