637637506945 has 4 divisors (see below), whose sum is σ = 765165008340. Its totient is φ = 510110005552.

The previous prime is 637637506907. The next prime is 637637506963. The reversal of 637637506945 is 549605736736.

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

It can be written as a sum of positive squares in 2 ways, for example, as 223993011841 + 413644495104 = 473279^2 + 643152^2 .

It is a cyclic number.

It is not a de Polignac number, because 637637506945 - 2⁷ = 637637506817 is a prime.

It is an unprimeable number.

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, 63763750690 + ... + 63763750699.

It is an arithmetic number, because the mean of its divisors is an integer number (191291252085).

Almost surely, 2^637637506945 is an apocalyptic number.

It is an amenable number.

637637506945 is a deficient number, since it is larger than the sum of its proper divisors (127527501395).

637637506945 is a wasteful number, since it uses less digits than its factorization.

637637506945 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 127527501394.

The product of its (nonzero) digits is 85730400, while the sum is 61.

The spelling of 637637506945 in words is "six hundred thirty-seven billion, six hundred thirty-seven million, five hundred six thousand, nine hundred forty-five".