1243235540 has 24 divisors (see below), whose sum is σ = 2666345472. Its totient is φ = 486713120.

The previous prime is 1243235533. The next prime is 1243235573. The reversal of 1243235540 is 455323421.

It is a happy number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 660356 + ... + 662235.

It is an arithmetic number, because the mean of its divisors is an integer number (111097728).

Almost surely, 2^1243235540 is an apocalyptic number.

1243235540 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1243235540 is an abundant number, since it is smaller than the sum of its proper divisors (1423109932).

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

1243235540 is a wasteful number, since it uses less digits than its factorization.

1243235540 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1322647 (or 1322645 counting only the distinct ones).

The product of its (nonzero) digits is 14400, while the sum is 29.

The square root of 1243235540 is about 35259.5453742671. The cubic root of 1243235540 is about 1075.2706843150.

Adding to 1243235540 its reverse (455323421), we get a palindrome (1698558961).

The spelling of 1243235540 in words is "one billion, two hundred forty-three million, two hundred thirty-five thousand, five hundred forty".