640765838857001 has 64 divisors (see below), whose sum is σ = 799559447258880. Its totient is φ = 504809672048640.

The previous prime is 640765838856961. The next prime is 640765838857033. The reversal of 640765838857001 is 100758838567046.

It is a cyclic number.

It is not a de Polignac number, because 640765838857001 - 2¹⁸ = 640765838594857 is a prime.

It is a super-2 number, since 2×640765838857001² (a number of 30 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (640765838157001) by changing a digit.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 1798043831 + ... + 1798400163.

It is an arithmetic number, because the mean of its divisors is an integer number (12493116363420).

Almost surely, 2^{640765838857001} is an apocalyptic number.

It is an amenable number.

640765838857001 is a deficient number, since it is larger than the sum of its proper divisors (158793608401879).

640765838857001 is a wasteful number, since it uses less digits than its factorization.

640765838857001 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 362346.

The product of its (nonzero) digits is 270950400, while the sum is 68.

The spelling of 640765838857001 in words is "six hundred forty trillion, seven hundred sixty-five billion, eight hundred thirty-eight million, eight hundred fifty-seven thousand, one".