21303413977 has 2 divisors, whose sum is σ = 21303413978. Its totient is φ = 21303413976.

The previous prime is 21303413953. The next prime is 21303414029. The reversal of 21303413977 is 77931430312.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 21123424921 + 179989056 = 145339^2 + 13416^2 .

It is a cyclic number.

It is not a de Polignac number, because 21303413977 - 2¹¹ = 21303411929 is a prime.

It is not a weakly prime, because it can be changed into another prime (21303413927) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10651706988 + 10651706989.

It is an arithmetic number, because the mean of its divisors is an integer number (10651706989).

Almost surely, 2^21303413977 is an apocalyptic number.

It is an amenable number.

21303413977 is a deficient number, since it is larger than the sum of its proper divisors (1).

21303413977 is an equidigital number, since it uses as much as digits as its factorization.

21303413977 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 95256, while the sum is 40.

The spelling of 21303413977 in words is "twenty-one billion, three hundred three million, four hundred thirteen thousand, nine hundred seventy-seven".