210021380 has 48 divisors (see below), whose sum is σ = 452390400. Its totient is φ = 81863808.

The previous prime is 210021379. The next prime is 210021389. The reversal of 210021380 is 83120012.

It is not an unprimeable number, because it can be changed into a prime (210021389) 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, 350321 + ... + 350919.

It is an arithmetic number, because the mean of its divisors is an integer number (9424800).

Almost surely, 2^210021380 is an apocalyptic number.

210021380 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

210021380 is an abundant number, since it is smaller than the sum of its proper divisors (242369020).

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

210021380 is a wasteful number, since it uses less digits than its factorization.

210021380 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1028 (or 1026 counting only the distinct ones).

The product of its (nonzero) digits is 96, while the sum is 17.

The square root of 210021380 is about 14492.1144074976. The cubic root of 210021380 is about 594.4123661873.

Adding to 210021380 its reverse (83120012), we get a palindrome (293141392).

The spelling of 210021380 in words is "two hundred ten million, twenty-one thousand, three hundred eighty".