30897128 has 8 divisors (see below), whose sum is σ = 57932130. Its totient is φ = 15448560.

The previous prime is 30897127. The next prime is 30897131. The reversal of 30897128 is 82179803.

It can be written as a sum of positive squares in only one way, i.e., 30228004 + 669124 = 5498^2 + 818^2 .

It is a tau number, because it is divible by the number of its divisors (8).

It is a junction number, because it is equal to n+sod(n) for n = 30897091 and 30897100.

It is not an unprimeable number, because it can be changed into a prime (30897121) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1931063 + ... + 1931078.

Almost surely, 2^30897128 is an apocalyptic number.

It is an amenable number.

30897128 is a deficient number, since it is larger than the sum of its proper divisors (27035002).

30897128 is a wasteful number, since it uses less digits than its factorization.

30897128 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3862147 (or 3862143 counting only the distinct ones).

The product of its (nonzero) digits is 24192, while the sum is 38.

The square root of 30897128 is about 5558.5185076601. The cubic root of 30897128 is about 313.7901961696.

The spelling of 30897128 in words is "thirty million, eight hundred ninety-seven thousand, one hundred twenty-eight".