81778045 has 8 divisors (see below), whose sum is σ = 100416096. Its totient is φ = 63900816.

The previous prime is 81778043. The next prime is 81778051. The reversal of 81778045 is 54087718.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 81778045 - 2¹ = 81778043 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 81777989 and 81778007.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81778043) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 189967 + ... + 190396.

It is an arithmetic number, because the mean of its divisors is an integer number (12552012).

Almost surely, 2^81778045 is an apocalyptic number.

It is an amenable number.

81778045 is a deficient number, since it is larger than the sum of its proper divisors (18638051).

81778045 is a wasteful number, since it uses less digits than its factorization.

81778045 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 380411.

The product of its (nonzero) digits is 62720, while the sum is 40.

The square root of 81778045 is about 9043.1214190676. The cubic root of 81778045 is about 434.0558108834.

The spelling of 81778045 in words is "eighty-one million, seven hundred seventy-eight thousand, forty-five".