30999987 has 6 divisors (see below), whose sum is σ = 44777772. Its totient is φ = 20666652.

The previous prime is 30999979. The next prime is 30999989. The reversal of 30999987 is 78999903.

It is a happy number.

It is not a de Polignac number, because 30999987 - 2³ = 30999979 is a prime.

It is not an unprimeable number, because it can be changed into a prime (30999989) 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 5 ways as a sum of consecutive naturals, for example, 1722213 + ... + 1722230.

It is an arithmetic number, because the mean of its divisors is an integer number (7462962).

Almost surely, 2^30999987 is an apocalyptic number.

30999987 is a deficient number, since it is larger than the sum of its proper divisors (13777785).

30999987 is a wasteful number, since it uses less digits than its factorization.

30999987 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3444449 (or 3444446 counting only the distinct ones).

The product of its (nonzero) digits is 1102248, while the sum is 54.

The square root of 30999987 is about 5567.7631953954. The cubic root of 30999987 is about 314.1380213274.

The spelling of 30999987 in words is "thirty million, nine hundred ninety-nine thousand, nine hundred eighty-seven".