640651786225127 has 4 divisors (see below), whose sum is σ = 668506211713200. Its totient is φ = 612797360737056.

The previous prime is 640651786225013. The next prime is 640651786225201. The reversal of 640651786225127 is 721522687156046.

640651786225127 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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

It is a cyclic number.

It is not a de Polignac number, because 640651786225127 - 2¹⁴ = 640651786208743 is a prime.

It is a super-2 number, since 2×640651786225127² (a number of 30 digits) contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 640651786225127.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (640651786225327) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 13927212744002 + ... + 13927212744047.

It is an arithmetic number, because the mean of its divisors is an integer number (167126552928300).

Almost surely, 2^{640651786225127} is an apocalyptic number.

640651786225127 is a deficient number, since it is larger than the sum of its proper divisors (27854425488073).

640651786225127 is a wasteful number, since it uses less digits than its factorization.

640651786225127 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 27854425488072.

The product of its (nonzero) digits is 67737600, while the sum is 62.

The spelling of 640651786225127 in words is "six hundred forty trillion, six hundred fifty-one billion, seven hundred eighty-six million, two hundred twenty-five thousand, one hundred twenty-seven".