1240001204521 has 2 divisors, whose sum is σ = 1240001204522. Its totient is φ = 1240001204520.

The previous prime is 1240001204483. The next prime is 1240001204537. The reversal of 1240001204521 is 1254021000421.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 633354938896 + 606646265625 = 795836^2 + 778875^2 .

It is a cyclic number.

It is not a de Polignac number, because 1240001204521 - 2²⁷ = 1239866986793 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 1240001204492 and 1240001204501.

It is not a weakly prime, because it can be changed into another prime (1240001204621) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 620000602260 + 620000602261.

It is an arithmetic number, because the mean of its divisors is an integer number (620000602261).

Almost surely, 2^{1240001204521} is an apocalyptic number.

It is an amenable number.

1240001204521 is a deficient number, since it is larger than the sum of its proper divisors (1).

1240001204521 is an equidigital number, since it uses as much as digits as its factorization.

1240001204521 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 640, while the sum is 22.

Adding to 1240001204521 its reverse (1254021000421), we get a palindrome (2494022204942).

The spelling of 1240001204521 in words is "one trillion, two hundred forty billion, one million, two hundred four thousand, five hundred twenty-one".