165511422403 has 4 divisors (see below), whose sum is σ = 165514602960. Its totient is φ = 165508241848.

The previous prime is 165511422397. The next prime is 165511422437. The reversal of 165511422403 is 304224115561.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 304224115561 = 36191 ⋅8406071.

It is a cyclic number.

It is not a de Polignac number, because 165511422403 - 2⁹ = 165511421891 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (165511422103) 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, 1510900 + ... + 1616737.

It is an arithmetic number, because the mean of its divisors is an integer number (41378650740).

Almost surely, 2^165511422403 is an apocalyptic number.

165511422403 is a deficient number, since it is larger than the sum of its proper divisors (3180557).

165511422403 is an equidigital number, since it uses as much as digits as its factorization.

165511422403 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3180556.

The product of its (nonzero) digits is 28800, while the sum is 34.

Adding to 165511422403 its reverse (304224115561), we get a palindrome (469735537964).

The spelling of 165511422403 in words is "one hundred sixty-five billion, five hundred eleven million, four hundred twenty-two thousand, four hundred three".