1028690 has 32 divisors (see below), whose sum is σ = 2053296. Its totient is φ = 368640.

The previous prime is 1028683. The next prime is 1028737. The reversal of 1028690 is 968201.

It can be written as a sum of positive squares in 8 ways, for example, as 10609 + 1018081 = 103^2 + 1009^2 .

It is a super-2 number, since 2×1028690² = 2116406232200, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (26).

It is a Curzon number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 5234 + ... + 5426.

2^1028690 is an apocalyptic number.

1028690 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

1028690 is a deficient number, since it is larger than the sum of its proper divisors (1024606).

1028690 is a wasteful number, since it uses less digits than its factorization.

1028690 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 254.

The product of its (nonzero) digits is 864, while the sum is 26.

The square root of 1028690 is about 1014.2435604923. The cubic root of 1028690 is about 100.9473306410.

The spelling of 1028690 in words is "one million, twenty-eight thousand, six hundred ninety".