308120813 has 24 divisors (see below), whose sum is σ = 416849664. Its totient is φ = 221617440.

The previous prime is 308120803. The next prime is 308120837. The reversal of 308120813 is 318021803.

It is a de Polignac number, because none of the positive numbers 2^k-308120813 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (308120803) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 2981 + ... + 25002.

It is an arithmetic number, because the mean of its divisors is an integer number (17368736).

Almost surely, 2^308120813 is an apocalyptic number.

It is an amenable number.

308120813 is a deficient number, since it is larger than the sum of its proper divisors (108728851).

308120813 is a wasteful number, since it uses less digits than its factorization.

308120813 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 28025 (or 28014 counting only the distinct ones).

The product of its (nonzero) digits is 1152, while the sum is 26.

The square root of 308120813 is about 17553.3704171022. The cubic root of 308120813 is about 675.4196296997.

It can be divided in two parts, 308 and 120813, that added together give a palindrome (121121).

The spelling of 308120813 in words is "three hundred eight million, one hundred twenty thousand, eight hundred thirteen".