170420728 has 16 divisors (see below), whose sum is σ = 336357000. Its totient is φ = 80725536.

The previous prime is 170420711. The next prime is 170420741. The reversal of 170420728 is 827024071.

It is a self number, because there is not a number n which added to its sum of digits gives 170420728.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 560443 + ... + 560746.

Almost surely, 2^170420728 is an apocalyptic number.

It is an amenable number.

170420728 is a deficient number, since it is larger than the sum of its proper divisors (165936272).

170420728 is a wasteful number, since it uses less digits than its factorization.

170420728 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1121214 (or 1121210 counting only the distinct ones).

The product of its (nonzero) digits is 6272, while the sum is 31.

The square root of 170420728 is about 13054.5290225270. The cubic root of 170420728 is about 554.4224470990.

Adding to 170420728 its reverse (827024071), we get a palindrome (997444799).

The spelling of 170420728 in words is "one hundred seventy million, four hundred twenty thousand, seven hundred twenty-eight".