81842046 has 128 divisors (see below), whose sum is σ = 211341312. Its totient is φ = 20736000.

The previous prime is 81842023. The next prime is 81842083. The reversal of 81842046 is 64024818.

It is a super-2 number, since 2×81842046² = 13396240986932232, which contains 22 as substring.

It is a Smith number, since the sum of its digits (33) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Harshad number since it is a multiple of its sum of digits (33).

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 81841998 and 81842016.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 452076 + ... + 452256.

It is an arithmetic number, because the mean of its divisors is an integer number (1651104).

Almost surely, 2^81842046 is an apocalyptic number.

81842046 is the 4836-th nonagonal number.

It is a practical number, because each smaller number is the sum of distinct divisors of 81842046, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (105670656).

81842046 is an abundant number, since it is smaller than the sum of its proper divisors (129499266).

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

81842046 is a wasteful number, since it uses less digits than its factorization.

81842046 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 258.

The product of its (nonzero) digits is 12288, while the sum is 33.

The square root of 81842046 is about 9046.6593834409. The cubic root of 81842046 is about 434.1690147067.

It can be divided in two parts, 8184 and 2046, that multiplied together give a square (16744464 = 4092²).

The spelling of 81842046 in words is "eighty-one million, eight hundred forty-two thousand, forty-six".