1220011001 has 32 divisors (see below), whose sum is σ = 1439762688. Its totient is φ = 1021501440.

The previous prime is 1220010977. The next prime is 1220011003. The reversal of 1220011001 is 1001100221.

It is not a de Polignac number, because 1220011001 - 2¹⁰ = 1220009977 is a prime.

It is a super-2 number, since 2×1220011001² = 2976853685122044002, which contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 1220011001.

It is not an unprimeable number, because it can be changed into a prime (1220011003) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 1867991 + ... + 1868643.

It is an arithmetic number, because the mean of its divisors is an integer number (44992584).

Almost surely, 2^1220011001 is an apocalyptic number.

1220011001 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

1220011001 is a deficient number, since it is larger than the sum of its proper divisors (219751687).

1220011001 is a wasteful number, since it uses less digits than its factorization.

1220011001 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 881.

The product of its (nonzero) digits is 4, while the sum is 8.

The square root of 1220011001 is about 34928.6558716479. The cubic root of 1220011001 is about 1068.5329418593.

Adding to 1220011001 its reverse (1001100221), we get a palindrome (2221111222).

The spelling of 1220011001 in words is "one billion, two hundred twenty million, eleven thousand, one".