1640135243647 has 4 divisors (see below), whose sum is σ = 1641179252376. Its totient is φ = 1639091234920.

The previous prime is 1640135243573. The next prime is 1640135243657. The reversal of 1640135243647 is 7463425310461.

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 1640135243647 - 2⁷ = 1640135243519 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 1640135243597 and 1640135243606.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1640135243657) 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, 522002008 + ... + 522005149.

It is an arithmetic number, because the mean of its divisors is an integer number (410294813094).

Almost surely, 2^{1640135243647} is an apocalyptic number.

1640135243647 is a deficient number, since it is larger than the sum of its proper divisors (1044008729).

1640135243647 is a wasteful number, since it uses less digits than its factorization.

1640135243647 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1044008728.

The product of its (nonzero) digits is 1451520, while the sum is 46.

The spelling of 1640135243647 in words is "one trillion, six hundred forty billion, one hundred thirty-five million, two hundred forty-three thousand, six hundred forty-seven".