221302400020 has 48 divisors (see below), whose sum is σ = 502560728208. Its totient is φ = 81372579840.

The previous prime is 221302399987. The next prime is 221302400021. The reversal of 221302400020 is 20004203122.

It can be written as a sum of positive squares in 8 ways, for example, as 12550272784 + 208752127236 = 112028^2 + 456894^2 .

It is a super-2 number, since 2×221302400020² (a number of 23 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 221302399967 and 221302400003.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (221302400021) 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, 1703239 + ... + 1828558.

It is an arithmetic number, because the mean of its divisors is an integer number (10470015171).

Almost surely, 2^221302400020 is an apocalyptic number.

221302400020 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

221302400020 is an abundant number, since it is smaller than the sum of its proper divisors (281258328188).

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

221302400020 is a wasteful number, since it uses less digits than its factorization.

221302400020 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3532060 (or 3532058 counting only the distinct ones).

The product of its (nonzero) digits is 192, while the sum is 16.

Adding to 221302400020 its reverse (20004203122), we get a palindrome (241306603142).

The spelling of 221302400020 in words is "two hundred twenty-one billion, three hundred two million, four hundred thousand, twenty".