165500556615651 has 4 divisors (see below), whose sum is σ = 220667408820872. Its totient is φ = 110333704410432.

The previous prime is 165500556615571. The next prime is 165500556615673. The reversal of 165500556615651 is 156516655005561.

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

It is not a de Polignac number, because 165500556615651 - 2¹³ = 165500556607459 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 165500556615591 and 165500556615600.

It is not an unprimeable number, because it can be changed into a prime (165500556615451) 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, 27583426102606 + ... + 27583426102611.

It is an arithmetic number, because the mean of its divisors is an integer number (55166852205218).

Almost surely, 2^{165500556615651} is an apocalyptic number.

165500556615651 is a deficient number, since it is larger than the sum of its proper divisors (55166852205221).

165500556615651 is an equidigital number, since it uses as much as digits as its factorization.

165500556615651 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 55166852205220.

The product of its (nonzero) digits is 20250000, while the sum is 57.

The spelling of 165500556615651 in words is "one hundred sixty-five trillion, five hundred billion, five hundred fifty-six million, six hundred fifteen thousand, six hundred fifty-one".