1216553 has 4 divisors (see below), whose sum is σ = 1310148. Its totient is φ = 1122960.

The previous prime is 1216547. The next prime is 1216559. The reversal of 1216553 is 3556121.

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

It is an interprime number because it is at equal distance from previous prime (1216547) and next prime (1216559).

It can be written as a sum of positive squares in 2 ways, for example, as 310249 + 906304 = 557^2 + 952^2 .

It is a cyclic number.

It is not a de Polignac number, because 1216553 - 2⁶ = 1216489 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1216559) 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, 46778 + ... + 46803.

It is an arithmetic number, because the mean of its divisors is an integer number (327537).

2^1216553 is an apocalyptic number.

1216553 is a gapful number since it is divisible by the number (13) formed by its first and last digit.

It is an amenable number.

1216553 is a deficient number, since it is larger than the sum of its proper divisors (93595).

1216553 is an equidigital number, since it uses as much as digits as its factorization.

1216553 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 93594.

The product of its digits is 900, while the sum is 23.

The square root of 1216553 is about 1102.9746143951. The cubic root of 1216553 is about 106.7522436076.

The spelling of 1216553 in words is "one million, two hundred sixteen thousand, five hundred fifty-three".