640757501 has 4 divisors (see below), whose sum is σ = 674481600. Its totient is φ = 607033404.

The previous prime is 640757497. The next prime is 640757561. The reversal of 640757501 is 105757046.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 105757046 = 2 ⋅52878523.

It is a cyclic number.

It is not a de Polignac number, because 640757501 - 2² = 640757497 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (640757561) by changing a digit.

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, 16862021 + ... + 16862058.

It is an arithmetic number, because the mean of its divisors is an integer number (168620400).

Almost surely, 2^640757501 is an apocalyptic number.

It is an amenable number.

640757501 is a deficient number, since it is larger than the sum of its proper divisors (33724099).

640757501 is a wasteful number, since it uses less digits than its factorization.

640757501 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 33724098.

The product of its (nonzero) digits is 29400, while the sum is 35.

The square root of 640757501 is about 25313.1882820004. The cubic root of 640757501 is about 862.1137391346.

The spelling of 640757501 in words is "six hundred forty million, seven hundred fifty-seven thousand, five hundred one".