640749148651 has 8 divisors (see below), whose sum is σ = 668666511360. Its totient is φ = 612836677992.

The previous prime is 640749148607. The next prime is 640749148661. The reversal of 640749148651 is 156841947046.

640749148651 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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 640749148651 - 2⁹ = 640749148139 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 640749148592 and 640749148601.

It is not an unprimeable number, because it can be changed into a prime (640749148601) 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, 954091 + ... + 1480468.

It is an arithmetic number, because the mean of its divisors is an integer number (83583313920).

Almost surely, 2^640749148651 is an apocalyptic number.

640749148651 is a deficient number, since it is larger than the sum of its proper divisors (27917362709).

640749148651 is a wasteful number, since it uses less digits than its factorization.

640749148651 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2446025.

The product of its (nonzero) digits is 5806080, while the sum is 55.

The spelling of 640749148651 in words is "six hundred forty billion, seven hundred forty-nine million, one hundred forty-eight thousand, six hundred fifty-one".