30728989 has 8 divisors (see below), whose sum is σ = 32185152. Its totient is φ = 29282880.

The previous prime is 30728987. The next prime is 30729001. The reversal of 30728989 is 98982703.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 30728989 - 2¹ = 30728987 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (30728987) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 4149 + ... + 8869.

It is an arithmetic number, because the mean of its divisors is an integer number (4023144).

Almost surely, 2^30728989 is an apocalyptic number.

It is an amenable number.

30728989 is a deficient number, since it is larger than the sum of its proper divisors (1456163).

30728989 is a wasteful number, since it uses less digits than its factorization.

30728989 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5027.

The product of its (nonzero) digits is 217728, while the sum is 46.

The square root of 30728989 is about 5543.3734314044. The cubic root of 30728989 is about 313.2199558364.

The spelling of 30728989 in words is "thirty million, seven hundred twenty-eight thousand, nine hundred eighty-nine".