243044020251 has 6 divisors (see below), whose sum is σ = 351063584820. Its totient is φ = 162029346828.

The previous prime is 243044020237. The next prime is 243044020301. The reversal of 243044020251 is 152020440342.

243044020251 is a `hidden beast` number, since 2 + 4 + 3 + 0 + 4 + 402 + 0 + 251 = 666.

It is a de Polignac number, because none of the positive numbers 2^k-243044020251 is a prime.

It is not an unprimeable number, because it can be changed into a prime (243044027251) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 13502445561 + ... + 13502445578.

It is an arithmetic number, because the mean of its divisors is an integer number (58510597470).

Almost surely, 2^243044020251 is an apocalyptic number.

243044020251 is a deficient number, since it is larger than the sum of its proper divisors (108019564569).

243044020251 is a wasteful number, since it uses less digits than its factorization.

243044020251 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 27004891145 (or 27004891142 counting only the distinct ones).

The product of its (nonzero) digits is 7680, while the sum is 27.

Adding to 243044020251 its reverse (152020440342), we get a palindrome (395064460593).

The spelling of 243044020251 in words is "two hundred forty-three billion, forty-four million, twenty thousand, two hundred fifty-one".