2001051421 has 4 divisors (see below), whose sum is σ = 2003323644. Its totient is φ = 1998779200.

The previous prime is 2001051389. The next prime is 2001051431. The reversal of 2001051421 is 1241501002.

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 107931321 + 1893120100 = 10389^2 + 43510^2 .

It is a cyclic number.

It is not a de Polignac number, because 2001051421 - 2⁵ = 2001051389 is a prime.

It is a super-2 number, since 2×2001051421² = 8008413578972238482, which contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 2001051395 and 2001051404.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2001051431) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1134790 + ... + 1136551.

It is an arithmetic number, because the mean of its divisors is an integer number (500830911).

Almost surely, 2^2001051421 is an apocalyptic number.

It is an amenable number.

2001051421 is a deficient number, since it is larger than the sum of its proper divisors (2272223).

2001051421 is an equidigital number, since it uses as much as digits as its factorization.

2001051421 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2272222.

The product of its (nonzero) digits is 80, while the sum is 16.

The square root of 2001051421 is about 44733.1132495828. The cubic root of 2001051421 is about 1260.1417957916.

Adding to 2001051421 its reverse (1241501002), we get a palindrome (3242552423).

The spelling of 2001051421 in words is "two billion, one million, fifty-one thousand, four hundred twenty-one".