21582773077 has 2 divisors, whose sum is σ = 21582773078. Its totient is φ = 21582773076.

The previous prime is 21582773027. The next prime is 21582773099. The reversal of 21582773077 is 77037728512.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 18940915876 + 2641857201 = 137626^2 + 51399^2 .

It is a cyclic number.

It is not a de Polignac number, because 21582773077 - 2¹¹ = 21582771029 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 21582773077.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21582773027) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10791386538 + 10791386539.

It is an arithmetic number, because the mean of its divisors is an integer number (10791386539).

Almost surely, 2^21582773077 is an apocalyptic number.

It is an amenable number.

21582773077 is a deficient number, since it is larger than the sum of its proper divisors (1).

21582773077 is an equidigital number, since it uses as much as digits as its factorization.

21582773077 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1152480, while the sum is 49.

The spelling of 21582773077 in words is "twenty-one billion, five hundred eighty-two million, seven hundred seventy-three thousand, seventy-seven".