30528640 has 32 divisors (see below), whose sum is σ = 72984060. Its totient is φ = 12211200.

The previous prime is 30528637. The next prime is 30528643. The reversal of 30528640 is 4682503.

It is an interprime number because it is at equal distance from previous prime (30528637) and next prime (30528643).

It can be written as a sum of positive squares in 2 ways, for example, as 30206016 + 322624 = 5496^2 + 568^2 .

It is a tau number, because it is divible by the number of its divisors (32).

It is a junction number, because it is equal to n+sod(n) for n = 30528599 and 30528608.

It is not an unprimeable number, because it can be changed into a prime (30528643) 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, 23211 + ... + 24490.

Almost surely, 2^30528640 is an apocalyptic number.

It is an amenable number.

30528640 is an abundant number, since it is smaller than the sum of its proper divisors (42455420).

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

30528640 is an equidigital number, since it uses as much as digits as its factorization.

30528640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 47720 (or 47708 counting only the distinct ones).

The product of its (nonzero) digits is 5760, while the sum is 28.

The square root of 30528640 is about 5525.2728439417. The cubic root of 30528640 is about 312.5377533055.

The spelling of 30528640 in words is "thirty million, five hundred twenty-eight thousand, six hundred forty".