308195988 has 12 divisors (see below), whose sum is σ = 719124000. Its totient is φ = 102731992.

The previous prime is 308195947. The next prime is 308195989. The reversal of 308195988 is 889591803.

It is a tau number, because it is divible by the number of its divisors (12).

It is a super-2 number, since 2×308195988² = 189969534038592288, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 308195988.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (308195989) 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, 12841488 + ... + 12841511.

It is an arithmetic number, because the mean of its divisors is an integer number (59927000).

Almost surely, 2^308195988 is an apocalyptic number.

It is an amenable number.

308195988 is an abundant number, since it is smaller than the sum of its proper divisors (410928012).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

308195988 is a wasteful number, since it uses less digits than its factorization.

308195988 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 25683006 (or 25683004 counting only the distinct ones).

The product of its (nonzero) digits is 622080, while the sum is 51.

The square root of 308195988 is about 17555.5116131658. The cubic root of 308195988 is about 675.4745546293.

The spelling of 308195988 in words is "three hundred eight million, one hundred ninety-five thousand, nine hundred eighty-eight".