30999990 has 64 divisors (see below), whose sum is σ = 87031296. Its totient is φ = 6918912.

The previous prime is 30999989. The next prime is 31000003. The reversal of 30999990 is 9999903.

It is a congruent number.

It is an unprimeable number.

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 31 ways as a sum of consecutive naturals, for example, 7314 + ... + 10746.

It is an arithmetic number, because the mean of its divisors is an integer number (1359864).

Almost surely, 2^30999990 is an apocalyptic number.

30999990 is a gapful number since it is divisible by the number (30) formed by its first and last digit.

It is a practical number, because each smaller number is the sum of distinct divisors of 30999990, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (43515648).

30999990 is an abundant number, since it is smaller than the sum of its proper divisors (56031306).

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

30999990 is a wasteful number, since it uses less digits than its factorization.

30999990 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3493.

The product of its (nonzero) digits is 177147, while the sum is 48.

The square root of 30999990 is about 5567.7634648034. The cubic root of 30999990 is about 314.1380314608.

The spelling of 30999990 in words is "thirty million, nine hundred ninety-nine thousand, nine hundred ninety".