30021989 has 4 divisors (see below), whose sum is σ = 31057260. Its totient is φ = 28986720.

The previous prime is 30021977. The next prime is 30022007. The reversal of 30021989 is 98912003.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 98912003 = 347 ⋅285049.

It can be written as a sum of positive squares in 2 ways, for example, as 21996100 + 8025889 = 4690^2 + 2833^2 .

It is a cyclic number.

It is not a de Polignac number, because 30021989 - 2¹² = 30017893 is a prime.

It is a super-2 number, since 2×30021989² = 1802639647032242, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (30021289) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 517592 + ... + 517649.

It is an arithmetic number, because the mean of its divisors is an integer number (7764315).

Almost surely, 2^30021989 is an apocalyptic number.

It is an amenable number.

30021989 is a deficient number, since it is larger than the sum of its proper divisors (1035271).

30021989 is a wasteful number, since it uses less digits than its factorization.

30021989 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1035270.

The product of its (nonzero) digits is 3888, while the sum is 32.

The square root of 30021989 is about 5479.2325192494. The cubic root of 30021989 is about 310.7991486499.

The spelling of 30021989 in words is "thirty million, twenty-one thousand, nine hundred eighty-nine".