210129640 has 48 divisors (see below), whose sum is σ = 549987300. Its totient is φ = 72043776.

The previous prime is 210129617. The next prime is 210129643. The reversal of 210129640 is 46921012.

210129640 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 2 ways, for example, as 170615844 + 39513796 = 13062^2 + 6286^2 .

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (210129643) 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, 51645 + ... + 55564.

Almost surely, 2^210129640 is an apocalyptic number.

210129640 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

210129640 is an abundant number, since it is smaller than the sum of its proper divisors (339857660).

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

210129640 is a wasteful number, since it uses less digits than its factorization.

210129640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 107234 (or 107223 counting only the distinct ones).

The product of its (nonzero) digits is 864, while the sum is 25.

The square root of 210129640 is about 14495.8490610243. The cubic root of 210129640 is about 594.5144828208.

The spelling of 210129640 in words is "two hundred ten million, one hundred twenty-nine thousand, six hundred forty".