7931428 has 6 divisors (see below), whose sum is σ = 13880006. Its totient is φ = 3965712.

The previous prime is 7931423. The next prime is 7931437. The reversal of 7931428 is 8241397.

It can be written as a sum of positive squares in only one way, i.e., 6927424 + 1004004 = 2632^2 + 1002^2 .

It is a junction number, because it is equal to n+sod(n) for n = 7931393 and 7931402.

It is not an unprimeable number, because it can be changed into a prime (7931423) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 991425 + ... + 991432.

Almost surely, 2^7931428 is an apocalyptic number.

It is an amenable number.

7931428 is a deficient number, since it is larger than the sum of its proper divisors (5948578).

7931428 is a wasteful number, since it uses less digits than its factorization.

7931428 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1982861 (or 1982859 counting only the distinct ones).

The product of its digits is 12096, while the sum is 34.

The square root of 7931428 is about 2816.2791054865. The cubic root of 7931428 is about 199.4269261670.

The spelling of 7931428 in words is "seven million, nine hundred thirty-one thousand, four hundred twenty-eight".