691428 has 24 divisors (see below), whose sum is σ = 1628032. Its totient is φ = 228384.

The previous prime is 691409. The next prime is 691433. The reversal of 691428 is 824196.

It is a junction number, because it is equal to n+sod(n) for n = 691395 and 691404.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1701 + ... + 2067.

2⁶⁹¹⁴²⁸ is an apocalyptic number.

It is an amenable number.

691428 is an abundant number, since it is smaller than the sum of its proper divisors (936604).

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

691428 is a wasteful number, since it uses less digits than its factorization.

691428 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 531 (or 529 counting only the distinct ones).

The product of its digits is 3456, while the sum is 30.

The square root of 691428 is about 831.5214970162. The cubic root of 691428 is about 88.4264766484.

The spelling of 691428 in words is "six hundred ninety-one thousand, four hundred twenty-eight".