81835782 has 24 divisors (see below), whose sum is σ = 190394136. Its totient is φ = 23381568.

The previous prime is 81835781. The next prime is 81835799. The reversal of 81835782 is 28753818.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (42).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81835781) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 138883 + ... + 139470.

It is an arithmetic number, because the mean of its divisors is an integer number (7933089).

Almost surely, 2^81835782 is an apocalyptic number.

81835782 is an abundant number, since it is smaller than the sum of its proper divisors (108558354).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

81835782 is a wasteful number, since it uses less digits than its factorization.

81835782 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 278372 (or 278365 counting only the distinct ones).

The product of its digits is 107520, while the sum is 42.

The square root of 81835782 is about 9046.3131716739. The cubic root of 81835782 is about 434.1579376616.

The spelling of 81835782 in words is "eighty-one million, eight hundred thirty-five thousand, seven hundred eighty-two".