210105640 has 16 divisors (see below), whose sum is σ = 472737780. Its totient is φ = 84042240.

The previous prime is 210105613. The next prime is 210105641. The reversal of 210105640 is 46501012.

It can be written as a sum of positive squares in 2 ways, for example, as 174081636 + 36024004 = 13194^2 + 6002^2 .

It is not an unprimeable number, because it can be changed into a prime (210105641) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2626281 + ... + 2626360.

Almost surely, 2^210105640 is an apocalyptic number.

210105640 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

210105640 is an abundant number, since it is smaller than the sum of its proper divisors (262632140).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

210105640 is a wasteful number, since it uses less digits than its factorization.

210105640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5252652 (or 5252648 counting only the distinct ones).

The product of its (nonzero) digits is 240, while the sum is 19.

The square root of 210105640 is about 14495.0212141963. The cubic root of 210105640 is about 594.4918477611.

Adding to 210105640 its reverse (46501012), we get a palindrome (256606652).

The spelling of 210105640 in words is "two hundred ten million, one hundred five thousand, six hundred forty".