81653478 has 8 divisors (see below), whose sum is σ = 163306968. Its totient is φ = 27217824.

The previous prime is 81653477. The next prime is 81653483. The reversal of 81653478 is 87435618.

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

81653478 is an admirable number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81653477) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 6804451 + ... + 6804462.

It is an arithmetic number, because the mean of its divisors is an integer number (20413371).

Almost surely, 2^81653478 is an apocalyptic number.

81653478 is a primitive abundant number, since it is smaller than the sum of its proper divisors, none of which is abundant.

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

81653478 is a wasteful number, since it uses less digits than its factorization.

81653478 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 13608918.

The product of its digits is 161280, while the sum is 42.

The square root of 81653478 is about 9036.2314047395. The cubic root of 81653478 is about 433.8353095387.

The spelling of 81653478 in words is "eighty-one million, six hundred fifty-three thousand, four hundred seventy-eight".