306387920 has 90 divisors (see below), whose sum is σ = 759187458. Its totient is φ = 114977664.

The previous prime is 306387869. The next prime is 306387937. The reversal of 306387920 is 29783603.

It can be written as a sum of positive squares in only one way, i.e., 245110336 + 61277584 = 15656^2 + 7828^2 .

It is a Harshad number since it is a multiple of its sum of digits (38).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 17 ways as a sum of consecutive naturals, for example, 2974589 + ... + 2974691.

Almost surely, 2^306387920 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 306387920, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (379593729).

306387920 is an abundant number, since it is smaller than the sum of its proper divisors (452799538).

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

306387920 is a wasteful number, since it uses less digits than its factorization.

306387920 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 257 (or 129 counting only the distinct ones).

The product of its (nonzero) digits is 54432, while the sum is 38.

The square root of 306387920 is about 17503.9401278684. The cubic root of 306387920 is about 674.1510461076.

The spelling of 306387920 in words is "three hundred six million, three hundred eighty-seven thousand, nine hundred twenty".