30138720 has 96 divisors (see below), whose sum is σ = 97560288. Its totient is φ = 7815168.

The previous prime is 30138709. The next prime is 30138791. The reversal of 30138720 is 2783103.

It is a tau number, because it is divible by the number of its divisors (96).

It is a Harshad number since it is a multiple of its sum of digits (24).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 16912 + ... + 18608.

It is an arithmetic number, because the mean of its divisors is an integer number (1016253).

Almost surely, 2^30138720 is an apocalyptic number.

30138720 is a gapful number since it is divisible by the number (30) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 30138720, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (48780144).

30138720 is an abundant number, since it is smaller than the sum of its proper divisors (67421568).

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

30138720 is a wasteful number, since it uses less digits than its factorization.

30138720 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1752 (or 1744 counting only the distinct ones).

The product of its (nonzero) digits is 1008, while the sum is 24.

The square root of 30138720 is about 5489.8743155012. The cubic root of 30138720 is about 311.2014424016.

It can be divided in two parts, 30 and 138720, that multiplied together give a square (4161600 = 2040²).

The spelling of 30138720 in words is "thirty million, one hundred thirty-eight thousand, seven hundred twenty".