27777645461 has 2 divisors, whose sum is σ = 27777645462. Its totient is φ = 27777645460.

The previous prime is 27777645439. The next prime is 27777645473. The reversal of 27777645461 is 16454677772.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 15010905361 + 12766740100 = 122519^2 + 112990^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-27777645461 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 27777645397 and 27777645406.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (27777645761) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 13888822730 + 13888822731.

It is an arithmetic number, because the mean of its divisors is an integer number (13888822731).

Almost surely, 2^27777645461 is an apocalyptic number.

It is an amenable number.

27777645461 is a deficient number, since it is larger than the sum of its proper divisors (1).

27777645461 is an equidigital number, since it uses as much as digits as its factorization.

27777645461 is an evil number, because the sum of its binary digits is even.

The product of its digits is 13829760, while the sum is 56.

The spelling of 27777645461 in words is "twenty-seven billion, seven hundred seventy-seven million, six hundred forty-five thousand, four hundred sixty-one".