30021842 has 4 divisors (see below), whose sum is σ = 45032766. Its totient is φ = 15010920.

The previous prime is 30021841. The next prime is 30021889. The reversal of 30021842 is 24812003.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 24812003 = 53 ⋅468151.

It can be written as a sum of positive squares in only one way, i.e., 30019441 + 2401 = 5479^2 + 49^2 .

It is not an unprimeable number, because it can be changed into a prime (30021841) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 7505459 + ... + 7505462.

Almost surely, 2^30021842 is an apocalyptic number.

30021842 is a deficient number, since it is larger than the sum of its proper divisors (15010924).

30021842 is a wasteful number, since it uses less digits than its factorization.

30021842 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 15010923.

The product of its (nonzero) digits is 384, while the sum is 20.

The square root of 30021842 is about 5479.2191049455. The cubic root of 30021842 is about 310.7986413823.

Adding to 30021842 its reverse (24812003), we get a palindrome (54833845).

The spelling of 30021842 in words is "thirty million, twenty-one thousand, eight hundred forty-two".