165340220123 has 4 divisors (see below), whose sum is σ = 178058698608. Its totient is φ = 152621741640.

The previous prime is 165340220107. The next prime is 165340220251. The reversal of 165340220123 is 321022043561.

It is a happy number.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 321022043561 = 11171 ⋅28737091.

It is a cyclic number.

It is not a de Polignac number, because 165340220123 - 2⁴ = 165340220107 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (165340220323) 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, 6359239223 + ... + 6359239248.

It is an arithmetic number, because the mean of its divisors is an integer number (44514674652).

Almost surely, 2^165340220123 is an apocalyptic number.

165340220123 is a gapful number since it is divisible by the number (13) formed by its first and last digit.

165340220123 is a deficient number, since it is larger than the sum of its proper divisors (12718478485).

165340220123 is a wasteful number, since it uses less digits than its factorization.

165340220123 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12718478484.

The product of its (nonzero) digits is 8640, while the sum is 29.

Adding to 165340220123 its reverse (321022043561), we get a palindrome (486362263684).

The spelling of 165340220123 in words is "one hundred sixty-five billion, three hundred forty million, two hundred twenty thousand, one hundred twenty-three".