7128947 has 4 divisors (see below), whose sum is σ = 8147376. Its totient is φ = 6110520.

The previous prime is 7128943. The next prime is 7128949. The reversal of 7128947 is 7498217.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 7498217 = 19 ⋅394643.

It is a cyclic number.

It is not a de Polignac number, because 7128947 - 2² = 7128943 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 7128947.

It is not an unprimeable number, because it can be changed into a prime (7128943) 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, 509204 + ... + 509217.

It is an arithmetic number, because the mean of its divisors is an integer number (2036844).

Almost surely, 2^7128947 is an apocalyptic number.

7128947 is a deficient number, since it is larger than the sum of its proper divisors (1018429).

7128947 is a wasteful number, since it uses less digits than its factorization.

7128947 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1018428.

The product of its digits is 28224, while the sum is 38.

The square root of 7128947 is about 2670.0088014836. The cubic root of 7128947 is about 192.4605822478.

The spelling of 7128947 in words is "seven million, one hundred twenty-eight thousand, nine hundred forty-seven".