72424342421 has 2 divisors, whose sum is σ = 72424342422. Its totient is φ = 72424342420.

The previous prime is 72424342409. The next prime is 72424342427. The reversal of 72424342421 is 12424342427.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 61729887025 + 10694455396 = 248455^2 + 103414^2 .

It is a cyclic number.

It is not a de Polignac number, because 72424342421 - 2¹⁸ = 72424080277 is a prime.

It is a super-2 number, since 2×72424342421² (a number of 23 digits) contains 22 as substring.

It is a Sophie Germain prime.

It is a Curzon number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (72424342427) 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, 36212171210 + 36212171211.

It is an arithmetic number, because the mean of its divisors is an integer number (36212171211).

Almost surely, 2^72424342421 is an apocalyptic number.

It is an amenable number.

72424342421 is a deficient number, since it is larger than the sum of its proper divisors (1).

72424342421 is an equidigital number, since it uses as much as digits as its factorization.

72424342421 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 86016, while the sum is 35.

Adding to 72424342421 its reverse (12424342427), we get a palindrome (84848684848).

The spelling of 72424342421 in words is "seventy-two billion, four hundred twenty-four million, three hundred forty-two thousand, four hundred twenty-one".