306813987 has 24 divisors (see below), whose sum is σ = 470293824. Its totient is φ = 199779048.

The previous prime is 306813973. The next prime is 306813989. The reversal of 306813987 is 789318603.

It is a happy number.

It is not a de Polignac number, because 306813987 - 2²² = 302619683 is a prime.

It is a Smith number, since the sum of its digits (45) coincides with the sum of the digits of its prime factors.

It is not an unprimeable number, because it can be changed into a prime (306813989) 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, 4233 + ... + 25130.

It is an arithmetic number, because the mean of its divisors is an integer number (19595576).

Almost surely, 2^306813987 is an apocalyptic number.

306813987 is a deficient number, since it is larger than the sum of its proper divisors (163479837).

306813987 is an equidigital number, since it uses as much as digits as its factorization.

306813987 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 29421 (or 29409 counting only the distinct ones).

The product of its (nonzero) digits is 217728, while the sum is 45.

The square root of 306813987 is about 17516.1065023024. The cubic root of 306813987 is about 674.4633957514.

The spelling of 306813987 in words is "three hundred six million, eight hundred thirteen thousand, nine hundred eighty-seven".