21877765423 has 2 divisors, whose sum is σ = 21877765424. Its totient is φ = 21877765422.

The previous prime is 21877765373. The next prime is 21877765451. The reversal of 21877765423 is 32456777812.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 21877765423 - 2⁹ = 21877764911 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21877765453) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10938882711 + 10938882712.

It is an arithmetic number, because the mean of its divisors is an integer number (10938882712).

Almost surely, 2^21877765423 is an apocalyptic number.

21877765423 is a deficient number, since it is larger than the sum of its proper divisors (1).

21877765423 is an equidigital number, since it uses as much as digits as its factorization.

21877765423 is an evil number, because the sum of its binary digits is even.

The product of its digits is 3951360, while the sum is 52.

The spelling of 21877765423 in words is "twenty-one billion, eight hundred seventy-seven million, seven hundred sixty-five thousand, four hundred twenty-three".