21422315977 has 2 divisors, whose sum is σ = 21422315978. Its totient is φ = 21422315976.

The previous prime is 21422315939. The next prime is 21422315983. The reversal of 21422315977 is 77951322412.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 14129839161 + 7292476816 = 118869^2 + 85396^2 .

It is a cyclic number.

It is not a de Polignac number, because 21422315977 - 2¹⁹ = 21421791689 is a prime.

It is not a weakly prime, because it can be changed into another prime (21422315917) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10711157988 + 10711157989.

It is an arithmetic number, because the mean of its divisors is an integer number (10711157989).

Almost surely, 2^21422315977 is an apocalyptic number.

It is an amenable number.

21422315977 is a deficient number, since it is larger than the sum of its proper divisors (1).

21422315977 is an equidigital number, since it uses as much as digits as its factorization.

21422315977 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 211680, while the sum is 43.

The spelling of 21422315977 in words is "twenty-one billion, four hundred twenty-two million, three hundred fifteen thousand, nine hundred seventy-seven".