30217728 has 80 divisors (see below), whose sum is σ = 81709056. Its totient is φ = 9922560.

The previous prime is 30217717. The next prime is 30217729. The reversal of 30217728 is 82771203.

It is a super-2 number, since 2×30217728² = 1826222170963968, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 30217695 and 30217704.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (30217729) 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, 158113 + ... + 158303.

Almost surely, 2^30217728 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 30217728, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (40854528).

30217728 is an abundant number, since it is smaller than the sum of its proper divisors (51491328).

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

30217728 is a wasteful number, since it uses less digits than its factorization.

30217728 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 315 (or 299 counting only the distinct ones).

The product of its (nonzero) digits is 4704, while the sum is 30.

The square root of 30217728 is about 5497.0653989197. The cubic root of 30217728 is about 311.4731410635.

The spelling of 30217728 in words is "thirty million, two hundred seventeen thousand, seven hundred twenty-eight".