210309993 has 16 divisors (see below), whose sum is σ = 327969600. Its totient is φ = 132827040.

The previous prime is 210309991. The next prime is 210310027. The reversal of 210309993 is 399903012.

It is not a de Polignac number, because 210309993 - 2¹ = 210309991 is a prime.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (210309991) 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, 204468 + ... + 205493.

It is an arithmetic number, because the mean of its divisors is an integer number (20498100).

Almost surely, 2^210309993 is an apocalyptic number.

It is an amenable number.

210309993 is a deficient number, since it is larger than the sum of its proper divisors (117659607).

210309993 is a wasteful number, since it uses less digits than its factorization.

210309993 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 409989 (or 409983 counting only the distinct ones).

The product of its (nonzero) digits is 13122, while the sum is 36.

The square root of 210309993 is about 14502.0685765859. The cubic root of 210309993 is about 594.6845235775.

The spelling of 210309993 in words is "two hundred ten million, three hundred nine thousand, nine hundred ninety-three".