1221122001 has 32 divisors (see below), whose sum is σ = 1879534080. Its totient is φ = 697420800.

The previous prime is 1221121991. The next prime is 1221122009. The reversal of 1221122001 is 1002211221.

It is not a de Polignac number, because 1221122001 - 2⁷ = 1221121873 is a prime.

It is a super-2 number, since 2×1221122001² = 2982277882652488002, which contains 22 as substring.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (1221122009) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 115966 + ... + 126056.

It is an arithmetic number, because the mean of its divisors is an integer number (58735440).

Almost surely, 2^1221122001 is an apocalyptic number.

1221122001 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

1221122001 is a deficient number, since it is larger than the sum of its proper divisors (658412079).

1221122001 is a wasteful number, since it uses less digits than its factorization.

1221122001 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10317.

The product of its (nonzero) digits is 16, while the sum is 12.

The square root of 1221122001 is about 34944.5560996273. The cubic root of 1221122001 is about 1068.8571957456.

Adding to 1221122001 its reverse (1002211221), we get a palindrome (2223333222).

The spelling of 1221122001 in words is "one billion, two hundred twenty-one million, one hundred twenty-two thousand, one".