1220212001 has 4 divisors (see below), whose sum is σ = 1220286852. Its totient is φ = 1220137152.

The previous prime is 1220211991. The next prime is 1220212013. The reversal of 1220212001 is 1002120221.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length, and also an emirpimes, since its reverse is a distinct semiprime: 1002120221 = 1471 ⋅681251.

It can be written as a sum of positive squares in 2 ways, for example, as 21390625 + 1198821376 = 4625^2 + 34624^2 .

It is a cyclic number.

It is not a de Polignac number, because 1220212001 - 2¹⁰ = 1220210977 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1220212801) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1436 + ... + 49421.

It is an arithmetic number, because the mean of its divisors is an integer number (305071713).

Almost surely, 2^1220212001 is an apocalyptic number.

It is an amenable number.

1220212001 is a deficient number, since it is larger than the sum of its proper divisors (74851).

1220212001 is an equidigital number, since it uses as much as digits as its factorization.

1220212001 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 74850.

The product of its (nonzero) digits is 16, while the sum is 11.

The square root of 1220212001 is about 34931.5330468046. The cubic root of 1220212001 is about 1068.5916198350.

Adding to 1220212001 its reverse (1002120221), we get a palindrome (2222332222).

The spelling of 1220212001 in words is "one billion, two hundred twenty million, two hundred twelve thousand, one".