30728641 has 2 divisors, whose sum is σ = 30728642. Its totient is φ = 30728640.

The previous prime is 30728629. The next prime is 30728669. The reversal of 30728641 is 14682703.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 30636225 + 92416 = 5535^2 + 304^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-30728641 is a prime.

It is not a weakly prime, because it can be changed into another prime (30728041) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 15364320 + 15364321.

It is an arithmetic number, because the mean of its divisors is an integer number (15364321).

Almost surely, 2^30728641 is an apocalyptic number.

It is an amenable number.

30728641 is a deficient number, since it is larger than the sum of its proper divisors (1).

30728641 is an equidigital number, since it uses as much as digits as its factorization.

30728641 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 8064, while the sum is 31.

The square root of 30728641 is about 5543.3420424866. The cubic root of 30728641 is about 313.2187734463.

The spelling of 30728641 in words is "thirty million, seven hundred twenty-eight thousand, six hundred forty-one".