1228520 has 16 divisors (see below), whose sum is σ = 2764260. Its totient is φ = 491392.

The previous prime is 1228519. The next prime is 1228537. The reversal of 1228520 is 258221.

1228520 is nontrivially palindromic in base 3.

It can be written as a sum of positive squares in 2 ways, for example, as 1196836 + 31684 = 1094^2 + 178^2 .

It is a super-2 number, since 2×1228520² = 3018522780800, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (20).

It is a junction number, because it is equal to n+sod(n) for n = 1228492 and 1228501.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 15317 + ... + 15396.

2^1228520 is an apocalyptic number.

1228520 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1228520 is an abundant number, since it is smaller than the sum of its proper divisors (1535740).

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

1228520 is a wasteful number, since it uses less digits than its factorization.

1228520 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 30724 (or 30720 counting only the distinct ones).

The product of its (nonzero) digits is 320, while the sum is 20.

The square root of 1228520 is about 1108.3862142773. The cubic root of 1228520 is about 107.1011359253.

Subtracting from 1228520 its reverse (258221), we obtain a cube (970299 = 99³).

The spelling of 1228520 in words is "one million, two hundred twenty-eight thousand, five hundred twenty".