210139986 has 32 divisors (see below), whose sum is σ = 483113088. Its totient is φ = 59690880.

The previous prime is 210139967. The next prime is 210139987. The reversal of 210139986 is 689931012.

210139986 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is not an unprimeable number, because it can be changed into a prime (210139987) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 7195 + ... + 21726.

It is an arithmetic number, because the mean of its divisors is an integer number (15097284).

Almost surely, 2^210139986 is an apocalyptic number.

210139986 is an abundant number, since it is smaller than the sum of its proper divisors (272973102).

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

210139986 is a wasteful number, since it uses less digits than its factorization.

210139986 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 29106.

The product of its (nonzero) digits is 23328, while the sum is 39.

The square root of 210139986 is about 14496.2059174116. The cubic root of 210139986 is about 594.5242398861.

The spelling of 210139986 in words is "two hundred ten million, one hundred thirty-nine thousand, nine hundred eighty-six".