30990923 has 4 divisors (see below), whose sum is σ = 31047120. Its totient is φ = 30934728.

The previous prime is 30990899. The next prime is 30990931. The reversal of 30990923 is 32909903.

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 30990923 - 2¹⁴ = 30974539 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (30990943) 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, 27263 + ... + 28376.

It is an arithmetic number, because the mean of its divisors is an integer number (7761780).

Almost surely, 2^30990923 is an apocalyptic number.

30990923 is a deficient number, since it is larger than the sum of its proper divisors (56197).

30990923 is an equidigital number, since it uses as much as digits as its factorization.

30990923 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 56196.

The product of its (nonzero) digits is 13122, while the sum is 35.

The square root of 30990923 is about 5566.9491644886. The cubic root of 30990923 is about 314.1074016954.

It can be divided in two parts, 30990 and 923, that added together give a palindrome (31913).

The spelling of 30990923 in words is "thirty million, nine hundred ninety thousand, nine hundred twenty-three".