81677377 has 2 divisors, whose sum is σ = 81677378. Its totient is φ = 81677376.

The previous prime is 81677341. The next prime is 81677411. The reversal of 81677377 is 77377618.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 78127921 + 3549456 = 8839^2 + 1884^2 .

It is a cyclic number.

It is not a de Polignac number, because 81677377 - 2¹¹ = 81675329 is a prime.

It is not a weakly prime, because it can be changed into another prime (81677317) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 40838688 + 40838689.

It is an arithmetic number, because the mean of its divisors is an integer number (40838689).

Almost surely, 2^81677377 is an apocalyptic number.

It is an amenable number.

81677377 is a deficient number, since it is larger than the sum of its proper divisors (1).

81677377 is an equidigital number, since it uses as much as digits as its factorization.

81677377 is an evil number, because the sum of its binary digits is even.

The product of its digits is 345744, while the sum is 46.

The square root of 81677377 is about 9037.5537066177. The cubic root of 81677377 is about 433.8776315517.

The spelling of 81677377 in words is "eighty-one million, six hundred seventy-seven thousand, three hundred seventy-seven".