1243400233421 has 4 divisors (see below), whose sum is σ = 1249648476000. Its totient is φ = 1237151990844.

The previous prime is 1243400233373. The next prime is 1243400233429. The reversal of 1243400233421 is 1243320043421.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1243400233421 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1243400233429) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3124120991 + ... + 3124121388.

It is an arithmetic number, because the mean of its divisors is an integer number (312412119000).

Almost surely, 2^{1243400233421} is an apocalyptic number.

It is an amenable number.

1243400233421 is a deficient number, since it is larger than the sum of its proper divisors (6248242579).

1243400233421 is an equidigital number, since it uses as much as digits as its factorization.

1243400233421 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6248242578.

The product of its (nonzero) digits is 13824, while the sum is 29.

Adding to 1243400233421 its reverse (1243320043421), we get a palindrome (2486720276842).

The spelling of 1243400233421 in words is "one trillion, two hundred forty-three billion, four hundred million, two hundred thirty-three thousand, four hundred twenty-one".