1220635 has 16 divisors (see below), whose sum is σ = 1602720. Its totient is φ = 887040.

The previous prime is 1220623. The next prime is 1220657. The reversal of 1220635 is 5360221.

It is a happy number.

It is not a de Polignac number, because 1220635 - 2⁷ = 1220507 is a prime.

1220635 is a lucky number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 5680 + ... + 5890.

It is an arithmetic number, because the mean of its divisors is an integer number (100170).

2^1220635 is an apocalyptic number.

1220635 is a deficient number, since it is larger than the sum of its proper divisors (382085).

1220635 is a wasteful number, since it uses less digits than its factorization.

It is an anagram of its base 9 representation: 1220635 = (2260351)₉.

1220635 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 318.

The product of its (nonzero) digits is 360, while the sum is 19.

The square root of 1220635 is about 1104.8235153182. The cubic root of 1220635 is about 106.8715084983.

Adding to 1220635 its reverse (5360221), we get a palindrome (6580856).

The spelling of 1220635 in words is "one million, two hundred twenty thousand, six hundred thirty-five".