1221322001 has 8 divisors (see below), whose sum is σ = 1233546600. Its totient is φ = 1209116160.

The previous prime is 1221321977. The next prime is 1221322013. The reversal of 1221322001 is 1002231221.

It is a happy number.

It can be written as a sum of positive squares in 4 ways, for example, as 29691601 + 1191630400 = 5449^2 + 34520^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1221322001 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1221322021) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 151841 + ... + 159681.

It is an arithmetic number, because the mean of its divisors is an integer number (154193325).

Almost surely, 2^1221322001 is an apocalyptic number.

It is an amenable number.

1221322001 is a deficient number, since it is larger than the sum of its proper divisors (12224599).

1221322001 is a wasteful number, since it uses less digits than its factorization.

1221322001 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9379.

The product of its (nonzero) digits is 48, while the sum is 14.

The square root of 1221322001 is about 34947.4176585338. The cubic root of 1221322001 is about 1068.9155463907.

Adding to 1221322001 its reverse (1002231221), we get a palindrome (2223553222).

The spelling of 1221322001 in words is "one billion, two hundred twenty-one million, three hundred twenty-two thousand, one".