1220120001 has 12 divisors (see below), whose sum is σ = 1765785060. Its totient is φ = 811848960.

The previous prime is 1220119993. The next prime is 1220120021. The reversal of 1220120001 is 1000210221.

It can be written as a sum of positive squares in 2 ways, for example, as 779749776 + 440370225 = 27924^2 + 20985^2 .

It is not a de Polignac number, because 1220120001 - 2³ = 1220119993 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (9).

It is not an unprimeable number, because it can be changed into a prime (1220120021) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 125416 + ... + 134793.

It is an arithmetic number, because the mean of its divisors is an integer number (147148755).

Almost surely, 2^1220120001 is an apocalyptic number.

It is an amenable number.

1220120001 is a deficient number, since it is larger than the sum of its proper divisors (545665059).

1220120001 is a wasteful number, since it uses less digits than its factorization.

1220120001 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 260736 (or 260733 counting only the distinct ones).

The product of its (nonzero) digits is 8, while the sum is 9.

The square root of 1220120001 is about 34930.2161602244. The cubic root of 1220120001 is about 1068.5647630539.

Adding to 1220120001 its reverse (1000210221), we get a palindrome (2220330222).

The spelling of 1220120001 in words is "one billion, two hundred twenty million, one hundred twenty thousand, one".