221042042120 has 64 divisors (see below), whose sum is σ = 509831083440. Its totient is φ = 86200012800.

The previous prime is 221042042113. The next prime is 221042042203. The reversal of 221042042120 is 21240240122.

It can be written as a sum of positive squares in 8 ways, for example, as 63666391684 + 157375650436 = 252322^2 + 396706^2 .

It is a Harshad number since it is a multiple of its sum of digits (20).

It is a junction number, because it is equal to n+sod(n) for n = 221042042092 and 221042042101.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 2336540 + ... + 2429300.

Almost surely, 2^221042042120 is an apocalyptic number.

221042042120 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 221042042120, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (254915541720).

221042042120 is an abundant number, since it is smaller than the sum of its proper divisors (288789041320).

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

221042042120 is a wasteful number, since it uses less digits than its factorization.

221042042120 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 94266 (or 94262 counting only the distinct ones).

The product of its (nonzero) digits is 512, while the sum is 20.

Adding to 221042042120 its reverse (21240240122), we get a palindrome (242282282242).

The spelling of 221042042120 in words is "two hundred twenty-one billion, forty-two million, forty-two thousand, one hundred twenty".