81746136 has 24 divisors (see below), whose sum is σ = 221395980. Its totient is φ = 27248688.

The previous prime is 81746123. The next prime is 81746143. The reversal of 81746136 is 63164718.

It is a tau number, because it is divible by the number of its divisors (24).

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a self number, because there is not a number n which added to its sum of digits gives 81746136.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 567610 + ... + 567753.

Almost surely, 2^81746136 is an apocalyptic number.

It is an amenable number.

81746136 is an abundant number, since it is smaller than the sum of its proper divisors (139649844).

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

81746136 is a wasteful number, since it uses less digits than its factorization.

81746136 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1135375 (or 1135368 counting only the distinct ones).

The product of its digits is 24192, while the sum is 36.

The square root of 81746136 is about 9041.3569777993. The cubic root of 81746136 is about 433.9993487500. Note that the first 3 decimals are identical.

The spelling of 81746136 in words is "eighty-one million, seven hundred forty-six thousand, one hundred thirty-six".