123361821 has 24 divisors (see below), whose sum is σ = 196743456. Its totient is φ = 73859040.

The previous prime is 123361781. The next prime is 123361829. The reversal of 123361821 is 128163321.

It is a happy number.

123361821 is a `hidden beast` number, since 1 + 23 + 3 + 618 + 21 = 666.

It is not a de Polignac number, because 123361821 - 2⁶ = 123361757 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (123361829) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 711 + ... + 15723.

It is an arithmetic number, because the mean of its divisors is an integer number (8197644).

Almost surely, 2^123361821 is an apocalyptic number.

123361821 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

123361821 is a deficient number, since it is larger than the sum of its proper divisors (73381635).

123361821 is a wasteful number, since it uses less digits than its factorization.

123361821 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 15113 (or 15110 counting only the distinct ones).

The product of its digits is 1728, while the sum is 27.

The square root of 123361821 is about 11106.8366783707. The cubic root of 123361821 is about 497.8061494515.

The spelling of 123361821 in words is "one hundred twenty-three million, three hundred sixty-one thousand, eight hundred twenty-one".