81777033 has 28 divisors (see below), whose sum is σ = 132056260. Its totient is φ = 50318496.

The previous prime is 81777023. The next prime is 81777037. The reversal of 81777033 is 33077718.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 36578304 + 45198729 = 6048^2 + 6723^2 .

It is not a de Polignac number, because 81777033 - 2⁸ = 81776777 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (81777037) by changing a digit.

It is a polite number, since it can be written in 27 ways as a sum of consecutive naturals, for example, 5163 + ... + 13791.

It is an arithmetic number, because the mean of its divisors is an integer number (4716295).

Almost surely, 2^81777033 is an apocalyptic number.

It is an amenable number.

81777033 is a deficient number, since it is larger than the sum of its proper divisors (50279227).

81777033 is an equidigital number, since it uses as much as digits as its factorization.

81777033 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8660 (or 8645 counting only the distinct ones).

The product of its (nonzero) digits is 24696, while the sum is 36.

The square root of 81777033 is about 9043.0654647636. The cubic root of 81777033 is about 434.0540204017.

The spelling of 81777033 in words is "eighty-one million, seven hundred seventy-seven thousand, thirty-three".