1213201001 has 4 divisors (see below), whose sum is σ = 1233089604. Its totient is φ = 1193312400.

The previous prime is 1213200997. The next prime is 1213201007. The reversal of 1213201001 is 1001023121.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 453647401 + 759553600 = 21299^2 + 27560^2 .

It is a cyclic number.

It is not a de Polignac number, because 1213201001 - 2² = 1213200997 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1213201007) 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 3 ways as a sum of consecutive naturals, for example, 9944210 + ... + 9944331.

It is an arithmetic number, because the mean of its divisors is an integer number (308272401).

Almost surely, 2^1213201001 is an apocalyptic number.

It is an amenable number.

1213201001 is a deficient number, since it is larger than the sum of its proper divisors (19888603).

1213201001 is an equidigital number, since it uses as much as digits as its factorization.

1213201001 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 19888602.

The product of its (nonzero) digits is 12, while the sum is 11.

The square root of 1213201001 is about 34831.0350262521. The cubic root of 1213201001 is about 1066.5410770865.

Adding to 1213201001 its reverse (1001023121), we get a palindrome (2214224122).

The spelling of 1213201001 in words is "one billion, two hundred thirteen million, two hundred one thousand, one".