16421699977 has 2 divisors, whose sum is σ = 16421699978. Its totient is φ = 16421699976.

The previous prime is 16421699971. The next prime is 16421700037. The reversal of 16421699977 is 77999612461.

16421699977 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 15106622281 + 1315077696 = 122909^2 + 36264^2 .

It is a cyclic number.

It is not a de Polignac number, because 16421699977 - 2¹⁵ = 16421667209 is a prime.

It is not a weakly prime, because it can be changed into another prime (16421699971) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 8210849988 + 8210849989.

It is an arithmetic number, because the mean of its divisors is an integer number (8210849989).

Almost surely, 2^16421699977 is an apocalyptic number.

It is an amenable number.

16421699977 is a deficient number, since it is larger than the sum of its proper divisors (1).

16421699977 is an equidigital number, since it uses as much as digits as its factorization.

16421699977 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 10287648, while the sum is 61.

The spelling of 16421699977 in words is "sixteen billion, four hundred twenty-one million, six hundred ninety-nine thousand, nine hundred seventy-seven".