306440640 has 336 divisors, whose sum is σ = 1219626720. Its totient is φ = 69795840.

The previous prime is 306440639. The next prime is 306440653. The reversal of 306440640 is 46044603.

It is a happy number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 538276 + ... + 538844.

Almost surely, 2^306440640 is an apocalyptic number.

306440640 is a gapful number since it is divisible by the number (30) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 306440640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (609813360).

306440640 is an abundant number, since it is smaller than the sum of its proper divisors (913186080).

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

306440640 is a wasteful number, since it uses less digits than its factorization.

306440640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 620 (or 607 counting only the distinct ones).

The product of its (nonzero) digits is 6912, while the sum is 27.

The square root of 306440640 is about 17505.4460097422. The cubic root of 306440640 is about 674.1897108226.

The spelling of 306440640 in words is "three hundred six million, four hundred forty thousand, six hundred forty".