123777842 has 4 divisors (see below), whose sum is σ = 185666766. Its totient is φ = 61888920.

The previous prime is 123777821. The next prime is 123777847. The reversal of 123777842 is 248777321.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in only one way, i.e., 121903681 + 1874161 = 11041^2 + 1369^2 .

It is a self number, because there is not a number n which added to its sum of digits gives 123777842.

It is not an unprimeable number, because it can be changed into a prime (123777847) 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, 30944459 + ... + 30944462.

Almost surely, 2^123777842 is an apocalyptic number.

123777842 is a deficient number, since it is larger than the sum of its proper divisors (61888924).

123777842 is an equidigital number, since it uses as much as digits as its factorization.

123777842 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 61888923.

The product of its digits is 131712, while the sum is 41.

The square root of 123777842 is about 11125.5490651024. The cubic root of 123777842 is about 498.3651161359.

The spelling of 123777842 in words is "one hundred twenty-three million, seven hundred seventy-seven thousand, eight hundred forty-two".