65601993640 has 32 divisors (see below), whose sum is σ = 147656769480. Its totient is φ = 26231502592.

The previous prime is 65601993553. The next prime is 65601993649. The reversal of 65601993640 is 4639910656.

It can be written as a sum of positive squares in 4 ways, for example, as 42237648324 + 23364345316 = 205518^2 + 152854^2 .

It is not an unprimeable number, because it can be changed into a prime (65601993649) 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, 175567 + ... + 402526.

Almost surely, 2^65601993640 is an apocalyptic number.

It is an amenable number.

65601993640 is an abundant number, since it is smaller than the sum of its proper divisors (82054775840).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

65601993640 is a wasteful number, since it uses less digits than its factorization.

65601993640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 580941 (or 580937 counting only the distinct ones).

The product of its (nonzero) digits is 1049760, while the sum is 49.

The spelling of 65601993640 in words is "sixty-five billion, six hundred one million, nine hundred ninety-three thousand, six hundred forty".