2123401021 has 4 divisors (see below), whose sum is σ = 2426744032. Its totient is φ = 1820058012.

The previous prime is 2123401019. The next prime is 2123401037. The reversal of 2123401021 is 1201043212.

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.

It is a cyclic number.

It is not a de Polignac number, because 2123401021 - 2¹ = 2123401019 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 2123400986 and 2123401004.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2123401061) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 151671495 + ... + 151671508.

It is an arithmetic number, because the mean of its divisors is an integer number (606686008).

Almost surely, 2^2123401021 is an apocalyptic number.

It is an amenable number.

2123401021 is a deficient number, since it is larger than the sum of its proper divisors (303343011).

2123401021 is an equidigital number, since it uses as much as digits as its factorization.

2123401021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 303343010.

The product of its (nonzero) digits is 96, while the sum is 16.

The square root of 2123401021 is about 46080.3756603611. The cubic root of 2123401021 is about 1285.3182496878.

Adding to 2123401021 its reverse (1201043212), we get a palindrome (3324444233).

The spelling of 2123401021 in words is "two billion, one hundred twenty-three million, four hundred one thousand, twenty-one".