1201021001 has 4 divisors (see below), whose sum is σ = 1208389392. Its totient is φ = 1193652612.

The previous prime is 1201020967. The next prime is 1201021007. The reversal of 1201021001 is 1001201021.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 1001201021 = 2557 ⋅391553.

It is a cyclic number.

It is not a de Polignac number, because 1201021001 - 2²⁶ = 1133912137 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 1201021001.

It is not an unprimeable number, because it can be changed into a prime (1201021007) 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, 3683951 + ... + 3684276.

It is an arithmetic number, because the mean of its divisors is an integer number (302097348).

Almost surely, 2^1201021001 is an apocalyptic number.

It is an amenable number.

1201021001 is a deficient number, since it is larger than the sum of its proper divisors (7368391).

1201021001 is an equidigital number, since it uses as much as digits as its factorization.

1201021001 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7368390.

The product of its (nonzero) digits is 4, while the sum is 8.

The square root of 1201021001 is about 34655.7498981049. The cubic root of 1201021001 is about 1062.9598658203.

Adding to 1201021001 its reverse (1001201021), we get a palindrome (2202222022).

The spelling of 1201021001 in words is "one billion, two hundred one million, twenty-one thousand, one".