21341511615421 has 2 divisors, whose sum is σ = 21341511615422. Its totient is φ = 21341511615420.

The previous prime is 21341511615371. The next prime is 21341511615443. The reversal of 21341511615421 is 12451611514312.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 16122393172900 + 5219118442521 = 4015270^2 + 2284539^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21341511615421 is a prime.

It is a super-2 number, since 2×21341511615421² (a number of 27 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21341511613421) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10670755807710 + 10670755807711.

It is an arithmetic number, because the mean of its divisors is an integer number (10670755807711).

Almost surely, 2^{21341511615421} is an apocalyptic number.

It is an amenable number.

21341511615421 is a deficient number, since it is larger than the sum of its proper divisors (1).

21341511615421 is an equidigital number, since it uses as much as digits as its factorization.

21341511615421 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 28800, while the sum is 37.

The spelling of 21341511615421 in words is "twenty-one trillion, three hundred forty-one billion, five hundred eleven million, six hundred fifteen thousand, four hundred twenty-one".