21325620367421 has 2 divisors, whose sum is σ = 21325620367422. Its totient is φ = 21325620367420.

The previous prime is 21325620367417. The next prime is 21325620367433. The reversal of 21325620367421 is 12476302652312.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 20012336455225 + 1313283912196 = 4473515^2 + 1145986^2 .

It is a cyclic number.

It is not a de Polignac number, because 21325620367421 - 2² = 21325620367417 is a prime.

It is a super-2 number, since 2×21325620367421² (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 (21325620307421) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10662810183710 + 10662810183711.

It is an arithmetic number, because the mean of its divisors is an integer number (10662810183711).

Almost surely, 2^{21325620367421} is an apocalyptic number.

It is an amenable number.

21325620367421 is a deficient number, since it is larger than the sum of its proper divisors (1).

21325620367421 is an equidigital number, since it uses as much as digits as its factorization.

21325620367421 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 725760, while the sum is 44.

The spelling of 21325620367421 in words is "twenty-one trillion, three hundred twenty-five billion, six hundred twenty million, three hundred sixty-seven thousand, four hundred twenty-one".