1223221540 has 24 divisors (see below), whose sum is σ = 2585133432. Its totient is φ = 486170880.

The previous prime is 1223221523. The next prime is 1223221541. The reversal of 1223221540 is 451223221.

It is a happy number.

It can be written as a sum of positive squares in 4 ways, for example, as 260112384 + 963109156 = 16128^2 + 31034^2 .

It is not an unprimeable number, because it can be changed into a prime (1223221541) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 191641 + ... + 197920.

It is an arithmetic number, because the mean of its divisors is an integer number (107713893).

Almost surely, 2^1223221540 is an apocalyptic number.

1223221540 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1223221540 is an abundant number, since it is smaller than the sum of its proper divisors (1361911892).

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

1223221540 is a wasteful number, since it uses less digits than its factorization.

1223221540 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 389727 (or 389725 counting only the distinct ones).

The product of its (nonzero) digits is 960, while the sum is 22.

The square root of 1223221540 is about 34974.5842005305. The cubic root of 1223221540 is about 1069.4694257156.

Adding to 1223221540 its reverse (451223221), we get a palindrome (1674444761).

The spelling of 1223221540 in words is "one billion, two hundred twenty-three million, two hundred twenty-one thousand, five hundred forty".