1216591 has 2 divisors, whose sum is σ = 1216592. Its totient is φ = 1216590.

The previous prime is 1216583. The next prime is 1216601. The reversal of 1216591 is 1956121.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 1216591 - 2³ = 1216583 is a prime.

It is a super-2 number, since 2×1216591² = 2960187322562, which contains 22 as substring.

It is a plaindrome in base 13.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1216561) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 608295 + 608296.

It is an arithmetic number, because the mean of its divisors is an integer number (608296).

2^1216591 is an apocalyptic number.

1216591 is a deficient number, since it is larger than the sum of its proper divisors (1).

1216591 is an equidigital number, since it uses as much as digits as its factorization.

1216591 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 540, while the sum is 25.

The square root of 1216591 is about 1102.9918404050. The cubic root of 1216591 is about 106.7533550931.

The spelling of 1216591 in words is "one million, two hundred sixteen thousand, five hundred ninety-one".