85176781 has 2 divisors, whose sum is σ = 85176782. Its totient is φ = 85176780.

The previous prime is 85176761. The next prime is 85176853. The reversal of 85176781 is 18767158.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 69455556 + 15721225 = 8334^2 + 3965^2 .

It is a cyclic number.

It is not a de Polignac number, because 85176781 - 2⁷ = 85176653 is a prime.

It is a super-2 number, since 2×85176781² = 14510168043043922, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (85176761) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 42588390 + 42588391.

It is an arithmetic number, because the mean of its divisors is an integer number (42588391).

Almost surely, 2^85176781 is an apocalyptic number.

It is an amenable number.

85176781 is a deficient number, since it is larger than the sum of its proper divisors (1).

85176781 is an equidigital number, since it uses as much as digits as its factorization.

85176781 is an evil number, because the sum of its binary digits is even.

The product of its digits is 94080, while the sum is 43.

The square root of 85176781 is about 9229.1267734277. The cubic root of 85176781 is about 439.9875702412.

The spelling of 85176781 in words is "eighty-five million, one hundred seventy-six thousand, seven hundred eighty-one".