165642635647 has 8 divisors (see below), whose sum is σ = 166750520192. Its totient is φ = 164534895000.

The previous prime is 165642635549. The next prime is 165642635657. The reversal of 165642635647 is 746536246561.

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 165642635647 - 2¹¹ = 165642633599 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (165642635657) 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 7 ways as a sum of consecutive naturals, for example, 3304828 + ... + 3354574.

It is an arithmetic number, because the mean of its divisors is an integer number (20843815024).

Almost surely, 2^165642635647 is an apocalyptic number.

165642635647 is a deficient number, since it is larger than the sum of its proper divisors (1107884545).

165642635647 is a wasteful number, since it uses less digits than its factorization.

165642635647 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 71949.

The product of its digits is 21772800, while the sum is 55.

The spelling of 165642635647 in words is "one hundred sixty-five billion, six hundred forty-two million, six hundred thirty-five thousand, six hundred forty-seven".