118211821 has 16 divisors (see below), whose sum is σ = 145805184. Its totient is φ = 93328704.

The previous prime is 118211813. The next prime is 118211827. The reversal of 118211821 is 128112811.

It is not a de Polignac number, because 118211821 - 2³ = 118211813 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (118211827) 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, 52311 + ... + 54523.

It is an arithmetic number, because the mean of its divisors is an integer number (9112824).

Almost surely, 2^118211821 is an apocalyptic number.

It is an amenable number.

118211821 is a deficient number, since it is larger than the sum of its proper divisors (27593363).

118211821 is a wasteful number, since it uses less digits than its factorization.

118211821 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2820.

The product of its digits is 256, while the sum is 25.

The square root of 118211821 is about 10872.5259714567. The cubic root of 118211821 is about 490.7801275644.

The spelling of 118211821 in words is "one hundred eighteen million, two hundred eleven thousand, eight hundred twenty-one".