1243400536 has 48 divisors (see below), whose sum is σ = 2830417200. Its totient is φ = 501533184.

The previous prime is 1243400533. The next prime is 1243400579. The reversal of 1243400536 is 6350043421.

It is a Harshad number since it is a multiple of its sum of digits (28).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1243400531) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 22231 + ... + 54598.

It is an arithmetic number, because the mean of its divisors is an integer number (58967025).

Almost surely, 2^1243400536 is an apocalyptic number.

It is an amenable number.

1243400536 is an abundant number, since it is smaller than the sum of its proper divisors (1587016664).

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

1243400536 is a wasteful number, since it uses less digits than its factorization.

1243400536 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 76876 (or 76855 counting only the distinct ones).

The product of its (nonzero) digits is 8640, while the sum is 28.

The square root of 1243400536 is about 35261.8850318584. The cubic root of 1243400536 is about 1075.3182503924.

Adding to 1243400536 its reverse (6350043421), we get a palindrome (7593443957).

The spelling of 1243400536 in words is "one billion, two hundred forty-three million, four hundred thousand, five hundred thirty-six".