81547000 has 32 divisors (see below), whose sum is σ = 190822320. Its totient is φ = 32618400.

The previous prime is 81546989. The next prime is 81547003. The reversal of 81547000 is 74518.

It is a Harshad number since it is a multiple of its sum of digits (25).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81547003) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 39774 + ... + 41773.

Almost surely, 2^81547000 is an apocalyptic number.

It is an amenable number.

81547000 is an abundant number, since it is smaller than the sum of its proper divisors (109275320).

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

81547000 is a wasteful number, since it uses less digits than its factorization.

81547000 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 81568 (or 81554 counting only the distinct ones).

The product of its (nonzero) digits is 1120, while the sum is 25.

The square root of 81547000 is about 9030.3377566955. The cubic root of 81547000 is about 433.6466504593.

The spelling of 81547000 in words is "eighty-one million, five hundred forty-seven thousand".