123777421 has 4 divisors (see below), whose sum is σ = 129159072. Its totient is φ = 118395772.

The previous prime is 123777377. The next prime is 123777491. The reversal of 123777421 is 124777321.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 123777421 - 2¹¹ = 123775373 is a prime.

It is a super-2 number, since 2×123777421² = 30641699898822482, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (123777491) 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 in 3 ways as a sum of consecutive naturals, for example, 2690791 + ... + 2690836.

It is an arithmetic number, because the mean of its divisors is an integer number (32289768).

Almost surely, 2^123777421 is an apocalyptic number.

It is an amenable number.

123777421 is a deficient number, since it is larger than the sum of its proper divisors (5381651).

123777421 is an equidigital number, since it uses as much as digits as its factorization.

123777421 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5381650.

The product of its digits is 16464, while the sum is 34.

The square root of 123777421 is about 11125.5301446718. The cubic root of 123777421 is about 498.3645511130.

The spelling of 123777421 in words is "one hundred twenty-three million, seven hundred seventy-seven thousand, four hundred twenty-one".