123355811 has 2 divisors, whose sum is σ = 123355812. Its totient is φ = 123355810.

The previous prime is 123355801. The next prime is 123355823. The reversal of 123355811 is 118553321.

It is a happy number.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 123355811 - 2²⁶ = 56246947 is a prime.

It is a super-2 number, since 2×123355811² = 30433312214935442, which contains 22 as substring.

It is a Sophie Germain prime.

It is a Chen prime.

It is equal to p_7021775 and since 123355811 and 7021775 have the same sum of digits, it is a Honaker prime.

It is not a weakly prime, because it can be changed into another prime (123355801) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 61677905 + 61677906.

It is an arithmetic number, because the mean of its divisors is an integer number (61677906).

Almost surely, 2^123355811 is an apocalyptic number.

123355811 is a deficient number, since it is larger than the sum of its proper divisors (1).

123355811 is an equidigital number, since it uses as much as digits as its factorization.

123355811 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 3600, while the sum is 29.

The square root of 123355811 is about 11106.5661209935. The cubic root of 123355811 is about 497.7980652011.

The spelling of 123355811 in words is "one hundred twenty-three million, three hundred fifty-five thousand, eight hundred eleven".