243121243040 has 96 divisors (see below), whose sum is σ = 625507097040. Its totient is φ = 88759148544.

The previous prime is 243121243039. The next prime is 243121243061. The reversal of 243121243040 is 40342121342.

It can be written as a sum of positive squares in 8 ways, for example, as 111767187856 + 131354055184 = 334316^2 + 362428^2 .

It is a Harshad number since it is a multiple of its sum of digits (26).

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 471539 + ... + 841778.

Almost surely, 2^243121243040 is an apocalyptic number.

243121243040 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

243121243040 is an abundant number, since it is smaller than the sum of its proper divisors (382385854000).

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

243121243040 is a wasteful number, since it uses less digits than its factorization.

243121243040 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1313434 (or 1313426 counting only the distinct ones).

The product of its (nonzero) digits is 4608, while the sum is 26.

Adding to 243121243040 its reverse (40342121342), we get a palindrome (283463364382).

The spelling of 243121243040 in words is "two hundred forty-three billion, one hundred twenty-one million, two hundred forty-three thousand, forty".