1220869 has 4 divisors (see below), whose sum is σ = 1314796. Its totient is φ = 1126944.

The previous prime is 1220839. The next prime is 1220893. The reversal of 1220869 is 9680221.

It is a happy number.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 476100 + 744769 = 690^2 + 863^2 .

It is not a de Polignac number, because 1220869 - 2¹¹ = 1218821 is a prime.

It is a super-2 number, since 2×1220869² = 2981042230322, which contains 22 as substring.

It is a Duffinian number.

1220869 is a lucky number.

It is a plaindrome in base 14.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1220819) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 46944 + ... + 46969.

It is an arithmetic number, because the mean of its divisors is an integer number (328699).

2^1220869 is an apocalyptic number.

It is an amenable number.

1220869 is a deficient number, since it is larger than the sum of its proper divisors (93927).

1220869 is an equidigital number, since it uses as much as digits as its factorization.

1220869 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 93926.

The product of its (nonzero) digits is 1728, while the sum is 28.

The square root of 1220869 is about 1104.9294095099. The cubic root of 1220869 is about 106.8783372760.

Subtracting from 1220869 its product of nonzero digits (1728), we obtain a triangular number (1219141 = T₁₅₆₁).

The spelling of 1220869 in words is "one million, two hundred twenty thousand, eight hundred sixty-nine".