1221022790001 has 45 divisors (see below), whose sum is σ = 2057800841291. Its totient is φ = 697634488656.

The previous prime is 1221022789981. The next prime is 1221022790027. The reversal of 1221022790001 is 1000972201221.

The square root of 1221022790001 is 1104999.

It is a perfect power (a square), and thus also a powerful number.

It can be written as a sum of positive squares in only one way, i.e., 1143669830625 + 77352959376 = 1069425^2 + 278124^2 .

It is not a de Polignac number, because 1221022790001 - 2²⁷ = 1220888572273 is a prime.

It is a super-2 number, since 2×1221022790001² (a number of 25 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1221022790401) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 44 ways as a sum of consecutive naturals, for example, 162431095 + ... + 162438611.

Almost surely, 2^{1221022790001} is an apocalyptic number.

1221022790001 is the 1104999-th square number.

1221022790001 is the 552500-th centered octagonal number.

It is an amenable number.

1221022790001 is a deficient number, since it is larger than the sum of its proper divisors (836778051290).

1221022790001 is an frugal number, since it uses more digits than its factorization.

1221022790001 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 15068 (or 7527 counting only the distinct ones).

The product of its (nonzero) digits is 1008, while the sum is 27.

Adding to 1221022790001 its reverse (1000972201221), we get a palindrome (2221994991222).

The spelling of 1221022790001 in words is "one trillion, two hundred twenty-one billion, twenty-two million, seven hundred ninety thousand, one".