505042778 has 4 divisors (see below), whose sum is σ = 757564170. Its totient is φ = 252521388.

The previous prime is 505042771. The next prime is 505042787. The reversal of 505042778 is 877240505.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 877240505 = 5 ⋅175448101.

It can be written as a sum of positive squares in only one way, i.e., 326633329 + 178409449 = 18073^2 + 13357^2 .

It is not an unprimeable number, because it can be changed into a prime (505042771) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 126260693 + ... + 126260696.

Almost surely, 2^505042778 is an apocalyptic number.

505042778 is a deficient number, since it is larger than the sum of its proper divisors (252521392).

505042778 is a wasteful number, since it uses less digits than its factorization.

505042778 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 252521391.

The product of its (nonzero) digits is 78400, while the sum is 38.

The square root of 505042778 is about 22473.1568320964. The cubic root of 505042778 is about 796.3599091693.

It can be divided in two parts, 5050427 and 78, that added together give a palindrome (5050505).

The spelling of 505042778 in words is "five hundred five million, forty-two thousand, seven hundred seventy-eight".