163023821 has 4 divisors (see below), whose sum is σ = 163150812. Its totient is φ = 162896832.

The previous prime is 163023803. The next prime is 163023827. The reversal of 163023821 is 128320361.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 128320361 = 13 ⋅9870797.

It can be written as a sum of positive squares in 2 ways, for example, as 145467721 + 17556100 = 12061^2 + 4190^2 .

It is a cyclic number.

It is not a de Polignac number, because 163023821 - 2²⁶ = 95914957 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 (163023827) 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 3 ways as a sum of consecutive naturals, for example, 61550 + ... + 64143.

It is an arithmetic number, because the mean of its divisors is an integer number (40787703).

Almost surely, 2^163023821 is an apocalyptic number.

It is an amenable number.

163023821 is a deficient number, since it is larger than the sum of its proper divisors (126991).

163023821 is a wasteful number, since it uses less digits than its factorization.

163023821 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 126990.

The product of its (nonzero) digits is 1728, while the sum is 26.

The square root of 163023821 is about 12768.0782030813. The cubic root of 163023821 is about 546.2821659621.

The spelling of 163023821 in words is "one hundred sixty-three million, twenty-three thousand, eight hundred twenty-one".