210234400021 has 4 divisors (see below), whose sum is σ = 222601129452. Its totient is φ = 197867670592.

The previous prime is 210234399983. The next prime is 210234400043. The reversal of 210234400021 is 120004432012.

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 64470795921 + 145763604100 = 253911^2 + 381790^2 .

It is a cyclic number.

It is not a de Polignac number, because 210234400021 - 2¹¹ = 210234397973 is a prime.

It is a super-3 number, since 3×210234400021³ (a number of 35 digits) contains 333 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (210234404021) 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, 6183364690 + ... + 6183364723.

It is an arithmetic number, because the mean of its divisors is an integer number (55650282363).

Almost surely, 2^210234400021 is an apocalyptic number.

It is an amenable number.

210234400021 is a deficient number, since it is larger than the sum of its proper divisors (12366729431).

210234400021 is a wasteful number, since it uses less digits than its factorization.

210234400021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12366729430.

The product of its (nonzero) digits is 384, while the sum is 19.

Adding to 210234400021 its reverse (120004432012), we get a palindrome (330238832033).

The spelling of 210234400021 in words is "two hundred ten billion, two hundred thirty-four million, four hundred thousand, twenty-one".