221423123020 has 96 divisors (see below), whose sum is σ = 536312689920. Its totient is φ = 75943376640.

The previous prime is 221423123017. The next prime is 221423123021. The reversal of 221423123020 is 20321324122.

It is a Harshad number since it is a multiple of its sum of digits (22).

It is a junction number, because it is equal to n+sod(n) for n = 221423122982 and 221423123000.

It is not an unprimeable number, because it can be changed into a prime (221423123021) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 832182 + ... + 1065538.

It is an arithmetic number, because the mean of its divisors is an integer number (5586590520).

Almost surely, 2^221423123020 is an apocalyptic number.

221423123020 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 221423123020, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (268156344960).

221423123020 is an abundant number, since it is smaller than the sum of its proper divisors (314889566900).

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

221423123020 is a wasteful number, since it uses less digits than its factorization.

221423123020 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 233623 (or 233621 counting only the distinct ones).

The product of its (nonzero) digits is 1152, while the sum is 22.

Adding to 221423123020 its reverse (20321324122), we get a palindrome (241744447142).

It can be divided in two parts, 221423 and 123020, that added together give a palindrome (344443).

The spelling of 221423123020 in words is "two hundred twenty-one billion, four hundred twenty-three million, one hundred twenty-three thousand, twenty".