1221288 has 32 divisors (see below), whose sum is σ = 3082560. Its totient is φ = 403200.

The previous prime is 1221251. The next prime is 1221289. The reversal of 1221288 is 8821221.

It is a Harshad number since it is a multiple of its sum of digits (24).

It is a nude number because it is divisible by every one of its digits.

It is an Ulam number.

It is not an unprimeable number, because it can be changed into a prime (1221289) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 3456 + ... + 3792.

It is an arithmetic number, because the mean of its divisors is an integer number (96330).

2^1221288 is an apocalyptic number.

It is an amenable number.

1221288 is an abundant number, since it is smaller than the sum of its proper divisors (1861272).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

1221288 is a wasteful number, since it uses less digits than its factorization.

1221288 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 497 (or 493 counting only the distinct ones).

The product of its digits is 512, while the sum is 24.

The square root of 1221288 is about 1105.1189981174. The cubic root of 1221288 is about 106.8905626939.

The spelling of 1221288 in words is "one million, two hundred twenty-one thousand, two hundred eighty-eight".