1212321001 has 4 divisors (see below), whose sum is σ = 1228928212. Its totient is φ = 1195713792.

The previous prime is 1212320987. The next prime is 1212321013. The reversal of 1212321001 is 1001232121.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 1001232121 = 67 ⋅14943763.

It can be written as a sum of positive squares in 2 ways, for example, as 258437776 + 953883225 = 16076^2 + 30885^2 .

It is a cyclic number.

It is not a de Polignac number, because 1212321001 - 2⁹ = 1212320489 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1212321041) 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, 8303496 + ... + 8303641.

It is an arithmetic number, because the mean of its divisors is an integer number (307232053).

Almost surely, 2^1212321001 is an apocalyptic number.

It is an amenable number.

1212321001 is a deficient number, since it is larger than the sum of its proper divisors (16607211).

1212321001 is an equidigital number, since it uses as much as digits as its factorization.

1212321001 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 16607210.

The product of its (nonzero) digits is 24, while the sum is 13.

The square root of 1212321001 is about 34818.4003222434. The cubic root of 1212321001 is about 1066.2831414910.

Adding to 1212321001 its reverse (1001232121), we get a palindrome (2213553122).

It can be divided in two parts, 12123 and 21001, that added together give a square (33124 = 182²).

The spelling of 1212321001 in words is "one billion, two hundred twelve million, three hundred twenty-one thousand, one".