1220291 has 6 divisors (see below), whose sum is σ = 1264692. Its totient is φ = 1177400.

The previous prime is 1220257. The next prime is 1220309. The reversal of 1220291 is 1920221.

It is a de Polignac number, because none of the positive numbers 2^k-1220291 is a prime.

It is a super-2 number, since 2×1220291² = 2978220249362, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1220251) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 116 + ... + 1566.

It is an arithmetic number, because the mean of its divisors is an integer number (210782).

2^1220291 is an apocalyptic number.

1220291 is a deficient number, since it is larger than the sum of its proper divisors (44401).

1220291 is an equidigital number, since it uses as much as digits as its factorization.

1220291 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1509 (or 1480 counting only the distinct ones).

The product of its (nonzero) digits is 72, while the sum is 17.

The square root of 1220291 is about 1104.6678233750. The cubic root of 1220291 is about 106.8614680267.

The spelling of 1220291 in words is "one million, two hundred twenty thousand, two hundred ninety-one".