1221241201 has 4 divisors (see below), whose sum is σ = 1225650292. Its totient is φ = 1216832112.

The previous prime is 1221241181. The next prime is 1221241213. The reversal of 1221241201 is 1021421221.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 1021421221 = 4597 ⋅222193.

It can be written as a sum of positive squares in 2 ways, for example, as 156850576 + 1064390625 = 12524^2 + 32625^2 .

It is a cyclic number.

It is not a de Polignac number, because 1221241201 - 2²⁹ = 684370289 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1227241201) 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, 2204130 + ... + 2204683.

It is an arithmetic number, because the mean of its divisors is an integer number (306412573).

Almost surely, 2^1221241201 is an apocalyptic number.

It is an amenable number.

1221241201 is a deficient number, since it is larger than the sum of its proper divisors (4409091).

1221241201 is an equidigital number, since it uses as much as digits as its factorization.

1221241201 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4409090.

The product of its (nonzero) digits is 64, while the sum is 16.

The square root of 1221241201 is about 34946.2616169455. The cubic root of 1221241201 is about 1068.8919734971.

Adding to 1221241201 its reverse (1021421221), we get a palindrome (2242662422).

The spelling of 1221241201 in words is "one billion, two hundred twenty-one million, two hundred forty-one thousand, two hundred one".