212161220 has 24 divisors (see below), whose sum is σ = 468988800. Its totient is φ = 80397792.

The previous prime is 212161211. The next prime is 212161267. The reversal of 212161220 is 22161212.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 278780 + ... + 279539.

It is an arithmetic number, because the mean of its divisors is an integer number (19541200).

Almost surely, 2^212161220 is an apocalyptic number.

212161220 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

212161220 is an abundant number, since it is smaller than the sum of its proper divisors (256827580).

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

212161220 is a wasteful number, since it uses less digits than its factorization.

212161220 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 558347 (or 558345 counting only the distinct ones).

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

The square root of 212161220 is about 14565.7550439378. The cubic root of 212161220 is about 596.4243071055.

The spelling of 212161220 in words is "two hundred twelve million, one hundred sixty-one thousand, two hundred twenty".