30947987 has 4 divisors (see below), whose sum is σ = 35369136. Its totient is φ = 26526840.

The previous prime is 30947981. The next prime is 30948011. The reversal of 30947987 is 78974903.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 30947987 - 2⁴ = 30947971 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (30947981) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2210564 + ... + 2210577.

It is an arithmetic number, because the mean of its divisors is an integer number (8842284).

Almost surely, 2^30947987 is an apocalyptic number.

30947987 is a deficient number, since it is larger than the sum of its proper divisors (4421149).

30947987 is an equidigital number, since it uses as much as digits as its factorization.

30947987 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4421148.

The product of its (nonzero) digits is 381024, while the sum is 47.

The square root of 30947987 is about 5563.0914966411. The cubic root of 30947987 is about 313.9622758850.

The spelling of 30947987 in words is "thirty million, nine hundred forty-seven thousand, nine hundred eighty-seven".