221331121020 has 36 divisors (see below), whose sum is σ = 671371067640. Its totient is φ = 59021632224.

The previous prime is 221331121007. The next prime is 221331121051. The reversal of 221331121020 is 20121133122.

221331121020 is a `hidden beast` number, since 221 + 331 + 12 + 102 + 0 = 666.

It is a tau number, because it is divible by the number of its divisors (36).

It is a Harshad number since it is a multiple of its sum of digits (18).

It is a junction number, because it is equal to n+sod(n) for n = 221331120984 and 221331121002.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 614808490 + ... + 614808849.

Almost surely, 2^221331121020 is an apocalyptic number.

221331121020 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

221331121020 is an abundant number, since it is smaller than the sum of its proper divisors (450039946620).

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

221331121020 is a wasteful number, since it uses less digits than its factorization.

221331121020 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1229617354 (or 1229617349 counting only the distinct ones).

The product of its (nonzero) digits is 144, while the sum is 18.

Adding to 221331121020 its reverse (20121133122), we get a palindrome (241452254142).

The spelling of 221331121020 in words is "two hundred twenty-one billion, three hundred thirty-one million, one hundred twenty-one thousand, twenty".