16432571655821 has 2 divisors, whose sum is σ = 16432571655822. Its totient is φ = 16432571655820.

The previous prime is 16432571655781. The next prime is 16432571655823. The reversal of 16432571655821 is 12855617523461.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 9213349622500 + 7219222033321 = 3035350^2 + 2686861^2 .

It is a cyclic number.

It is not a de Polignac number, because 16432571655821 - 2⁶ = 16432571655757 is a prime.

It is a super-2 number, since 2×16432571655821² (a number of 27 digits) contains 22 as substring.

Together with 16432571655823, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (16432571655823) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 8216285827910 + 8216285827911.

It is an arithmetic number, because the mean of its divisors is an integer number (8216285827911).

Almost surely, 2^{16432571655821} is an apocalyptic number.

It is an amenable number.

16432571655821 is a deficient number, since it is larger than the sum of its proper divisors (1).

16432571655821 is an equidigital number, since it uses as much as digits as its factorization.

16432571655821 is an evil number, because the sum of its binary digits is even.

The product of its digits is 12096000, while the sum is 56.

The spelling of 16432571655821 in words is "sixteen trillion, four hundred thirty-two billion, five hundred seventy-one million, six hundred fifty-five thousand, eight hundred twenty-one".