210436490021 has 4 divisors (see below), whose sum is σ = 210437444844. Its totient is φ = 210435535200.

The previous prime is 210436490009. The next prime is 210436490101. The reversal of 210436490021 is 120094634012.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It can be written as a sum of positive squares in 2 ways, for example, as 131033140225 + 79403349796 = 361985^2 + 281786^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-210436490021 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 210436490021.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (210436690021) 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, 40361 + ... + 650001.

It is an arithmetic number, because the mean of its divisors is an integer number (52609361211).

Almost surely, 2^210436490021 is an apocalyptic number.

It is an amenable number.

210436490021 is a deficient number, since it is larger than the sum of its proper divisors (954823).

210436490021 is an equidigital number, since it uses as much as digits as its factorization.

210436490021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 954822.

The product of its (nonzero) digits is 10368, while the sum is 32.

The spelling of 210436490021 in words is "two hundred ten billion, four hundred thirty-six million, four hundred ninety thousand, twenty-one".