2123402021 has 12 divisors (see below), whose sum is σ = 2399279328. Its totient is φ = 1874839824.

The previous prime is 2123401997. The next prime is 2123402081. The reversal of 2123402021 is 1202043212.

It is not a de Polignac number, because 2123402021 - 2⁶ = 2123401957 is a prime.

It is a super-3 number, since 3×2123402021³ (a number of 29 digits) contains 333 as substring. Note that it is a super-d number also for d = 2.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2123402081) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 269255 + ... + 277028.

It is an arithmetic number, because the mean of its divisors is an integer number (199939944).

Almost surely, 2^2123402021 is an apocalyptic number.

It is an amenable number.

2123402021 is a deficient number, since it is larger than the sum of its proper divisors (275877307).

2123402021 is a wasteful number, since it uses less digits than its factorization.

2123402021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 546332 (or 546319 counting only the distinct ones).

The product of its (nonzero) digits is 192, while the sum is 17.

The square root of 2123402021 is about 46080.3865109658. The cubic root of 2123402021 is about 1285.3184514582.

Adding to 2123402021 its reverse (1202043212), we get a palindrome (3325445233).

The spelling of 2123402021 in words is "two billion, one hundred twenty-three million, four hundred two thousand, twenty-one".