305778013 has 4 divisors (see below), whose sum is σ = 305813500. Its totient is φ = 305742528.

The previous prime is 305777981. The next prime is 305778029. The reversal of 305778013 is 310877503.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length, and also an emirpimes, since its reverse is a distinct semiprime: 310877503 = 2557 ⋅121579.

It can be written as a sum of positive squares in 2 ways, for example, as 117896164 + 187881849 = 10858^2 + 13707^2 .

It is a cyclic number.

It is not a de Polignac number, because 305778013 - 2⁵ = 305777981 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 305778013.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (305778713) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 4363 + ... + 25111.

It is an arithmetic number, because the mean of its divisors is an integer number (76453375).

Almost surely, 2^305778013 is an apocalyptic number.

It is an amenable number.

305778013 is a deficient number, since it is larger than the sum of its proper divisors (35487).

305778013 is a wasteful number, since it uses less digits than its factorization.

305778013 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 35486.

The product of its (nonzero) digits is 17640, while the sum is 34.

The square root of 305778013 is about 17486.5094572931. The cubic root of 305778013 is about 673.7034190451.

The spelling of 305778013 in words is "three hundred five million, seven hundred seventy-eight thousand, thirteen".