21869395277 has 2 divisors, whose sum is σ = 21869395278. Its totient is φ = 21869395276.

The previous prime is 21869395237. The next prime is 21869395283. The reversal of 21869395277 is 77259396812.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 19200536356 + 2668858921 = 138566^2 + 51661^2 .

It is a cyclic number.

It is not a de Polignac number, because 21869395277 - 2⁶ = 21869395213 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21869395237) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10934697638 + 10934697639.

It is an arithmetic number, because the mean of its divisors is an integer number (10934697639).

Almost surely, 2^21869395277 is an apocalyptic number.

It is an amenable number.

21869395277 is a deficient number, since it is larger than the sum of its proper divisors (1).

21869395277 is an equidigital number, since it uses as much as digits as its factorization.

21869395277 is an evil number, because the sum of its binary digits is even.

The product of its digits is 11430720, while the sum is 59.

The spelling of 21869395277 in words is "twenty-one billion, eight hundred sixty-nine million, three hundred ninety-five thousand, two hundred seventy-seven".