2121020218 has 4 divisors (see below), whose sum is σ = 3181530330. Its totient is φ = 1060510108.

The previous prime is 2121020201. The next prime is 2121020219. The reversal of 2121020218 is 8120201212.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in only one way, i.e., 1919578969 + 201441249 = 43813^2 + 14193^2 .

It is a junction number, because it is equal to n+sod(n) for n = 2121020195 and 2121020204.

It is not an unprimeable number, because it can be changed into a prime (2121020219) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 530255053 + ... + 530255056.

Almost surely, 2^2121020218 is an apocalyptic number.

2121020218 is a deficient number, since it is larger than the sum of its proper divisors (1060510112).

2121020218 is a wasteful number, since it uses less digits than its factorization.

2121020218 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1060510111.

The product of its (nonzero) digits is 128, while the sum is 19.

The square root of 2121020218 is about 46054.5352598417. The cubic root of 2121020218 is about 1284.8376945302.

The spelling of 2121020218 in words is "two billion, one hundred twenty-one million, twenty thousand, two hundred eighteen".