1231021001 has 16 divisors (see below), whose sum is σ = 1489138560. Its totient is φ = 994083840.

The previous prime is 1231020929. The next prime is 1231021009. The reversal of 1231021001 is 1001201321.

It is a cyclic number.

It is not a de Polignac number, because 1231021001 - 2¹⁴ = 1231004617 is a prime.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (1231021009) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1496 + ... + 49641.

It is an arithmetic number, because the mean of its divisors is an integer number (93071160).

Almost surely, 2^1231021001 is an apocalyptic number.

It is an amenable number.

1231021001 is a deficient number, since it is larger than the sum of its proper divisors (258117559).

1231021001 is a wasteful number, since it uses less digits than its factorization.

1231021001 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 51344.

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

The square root of 1231021001 is about 35085.9088666661. The cubic root of 1231021001 is about 1071.7376491108.

Adding to 1231021001 its reverse (1001201321), we get a palindrome (2232222322).

The spelling of 1231021001 in words is "one billion, two hundred thirty-one million, twenty-one thousand, one".