1200122001 has 20 divisors (see below), whose sum is σ = 1930682292. Its totient is φ = 738535968.

The previous prime is 1200121963. The next prime is 1200122039. The reversal of 1200122001 is 1002210021.

It is an interprime number because it is at equal distance from previous prime (1200121963) and next prime (1200122039).

It can be written as a sum of positive squares in 2 ways, for example, as 243828225 + 956293776 = 15615^2 + 30924^2 .

It is not a de Polignac number, because 1200122001 - 2¹⁴ = 1200105617 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 (1200124001) by changing a digit.

It is a polite number, since it can be written in 19 ways as a sum of consecutive naturals, for example, 568806 + ... + 570911.

Almost surely, 2^1200122001 is an apocalyptic number.

It is an amenable number.

1200122001 is a deficient number, since it is larger than the sum of its proper divisors (730560291).

1200122001 is a wasteful number, since it uses less digits than its factorization.

1200122001 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1139742 (or 1139733 counting only the distinct ones).

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

The square root of 1200122001 is about 34642.7770393772. Note that the first 3 decimals coincide. The cubic root of 1200122001 is about 1062.6945805756.

Adding to 1200122001 its reverse (1002210021), we get a palindrome (2202332022).

It can be divided in two parts, 1200 and 122001, that added together give a square (123201 = 351²).

The spelling of 1200122001 in words is "one billion, two hundred million, one hundred twenty-two thousand, one".