21759477967 has 2 divisors, whose sum is σ = 21759477968. Its totient is φ = 21759477966.

The previous prime is 21759477959. The next prime is 21759478001. The reversal of 21759477967 is 76977495712.

It is a happy number.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 21759477967 - 2³ = 21759477959 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 21759477899 and 21759477908.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21759477907) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10879738983 + 10879738984.

It is an arithmetic number, because the mean of its divisors is an integer number (10879738984).

Almost surely, 2^21759477967 is an apocalyptic number.

21759477967 is a deficient number, since it is larger than the sum of its proper divisors (1).

21759477967 is an equidigital number, since it uses as much as digits as its factorization.

21759477967 is an evil number, because the sum of its binary digits is even.

The product of its digits is 46675440, while the sum is 64.

The spelling of 21759477967 in words is "twenty-one billion, seven hundred fifty-nine million, four hundred seventy-seven thousand, nine hundred sixty-seven".