1240143812821 has 2 divisors, whose sum is σ = 1240143812822. Its totient is φ = 1240143812820.

The previous prime is 1240143812819. The next prime is 1240143812909. The reversal of 1240143812821 is 1282183410421.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 988405802596 + 251738010225 = 994186^2 + 501735^2 .

It is a cyclic number.

It is not a de Polignac number, because 1240143812821 - 2¹ = 1240143812819 is a prime.

Together with 1240143812819, it forms a pair of twin primes.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1240143810821) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 620071906410 + 620071906411.

It is an arithmetic number, because the mean of its divisors is an integer number (620071906411).

Almost surely, 2^{1240143812821} is an apocalyptic number.

It is an amenable number.

1240143812821 is a deficient number, since it is larger than the sum of its proper divisors (1).

1240143812821 is an equidigital number, since it uses as much as digits as its factorization.

1240143812821 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 24576, while the sum is 37.

The spelling of 1240143812821 in words is "one trillion, two hundred forty billion, one hundred forty-three million, eight hundred twelve thousand, eight hundred twenty-one".