211878380 has 24 divisors (see below), whose sum is σ = 508508448. Its totient is φ = 72643968.

The previous prime is 211878377. The next prime is 211878431. The reversal of 211878380 is 83878112.

It is a super-2 number, since 2×211878380² = 89784895822848800, which contains 22 as substring.

It is a Smith number, since the sum of its digits (38) coincides with the sum of the digits of its prime factors.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 756569 + ... + 756848.

It is an arithmetic number, because the mean of its divisors is an integer number (21187852).

Almost surely, 2^211878380 is an apocalyptic number.

211878380 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

211878380 is an abundant number, since it is smaller than the sum of its proper divisors (296630068).

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

211878380 is a wasteful number, since it uses less digits than its factorization.

211878380 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1513433 (or 1513431 counting only the distinct ones).

The product of its (nonzero) digits is 21504, while the sum is 38.

The square root of 211878380 is about 14556.0427314569. The cubic root of 211878380 is about 596.1591507775.

The spelling of 211878380 in words is "two hundred eleven million, eight hundred seventy-eight thousand, three hundred eighty".