16731507421 has 2 divisors, whose sum is σ = 16731507422. Its totient is φ = 16731507420.

The previous prime is 16731507391. The next prime is 16731507433. The reversal of 16731507421 is 12470513761.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 14644388196 + 2087119225 = 121014^2 + 45685^2 .

It is a cyclic number.

It is not a de Polignac number, because 16731507421 - 2¹⁷ = 16731376349 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (16731507451) 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, 8365753710 + 8365753711.

It is an arithmetic number, because the mean of its divisors is an integer number (8365753711).

Almost surely, 2^16731507421 is an apocalyptic number.

It is an amenable number.

16731507421 is a deficient number, since it is larger than the sum of its proper divisors (1).

16731507421 is an equidigital number, since it uses as much as digits as its factorization.

16731507421 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 35280, while the sum is 37.

The spelling of 16731507421 in words is "sixteen billion, seven hundred thirty-one million, five hundred seven thousand, four hundred twenty-one".