81733277 has 2 divisors, whose sum is σ = 81733278. Its totient is φ = 81733276.

The previous prime is 81733247. The next prime is 81733279. The reversal of 81733277 is 77233718.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 73633561 + 8099716 = 8581^2 + 2846^2 .

It is a cyclic number.

It is not a de Polignac number, because 81733277 - 2²² = 77538973 is a prime.

Together with 81733279, it forms a pair of twin primes.

It is a Chen prime.

It is a self number, because there is not a number n which added to its sum of digits gives 81733277.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (81733279) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 40866638 + 40866639.

It is an arithmetic number, because the mean of its divisors is an integer number (40866639).

Almost surely, 2^81733277 is an apocalyptic number.

It is an amenable number.

81733277 is a deficient number, since it is larger than the sum of its proper divisors (1).

81733277 is an equidigital number, since it uses as much as digits as its factorization.

81733277 is an evil number, because the sum of its binary digits is even.

The product of its digits is 49392, while the sum is 38.

The square root of 81733277 is about 9040.6458287005. The cubic root of 81733277 is about 433.9765909351.

The spelling of 81733277 in words is "eighty-one million, seven hundred thirty-three thousand, two hundred seventy-seven".