1243042400 has 36 divisors (see below), whose sum is σ = 3034579212. Its totient is φ = 497216640.

The previous prime is 1243042393. The next prime is 1243042421. The reversal of 1243042400 is 42403421.

It is a Harshad number since it is a multiple of its sum of digits (20).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 776102 + ... + 777701.

It is an arithmetic number, because the mean of its divisors is an integer number (84293867).

Almost surely, 2^1243042400 is an apocalyptic number.

1243042400 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1243042400 is an abundant number, since it is smaller than the sum of its proper divisors (1791536812).

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

1243042400 is a wasteful number, since it uses less digits than its factorization.

1243042400 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1553823 (or 1553810 counting only the distinct ones).

The product of its (nonzero) digits is 768, while the sum is 20.

The square root of 1243042400 is about 35256.8064350701. The cubic root of 1243042400 is about 1075.2149993626.

Adding to 1243042400 its reverse (42403421), we get a palindrome (1285445821).

The spelling of 1243042400 in words is "one billion, two hundred forty-three million, forty-two thousand, four hundred".