81373486 has 4 divisors (see below), whose sum is σ = 122060232. Its totient is φ = 40686742.

The previous prime is 81373483. The next prime is 81373493. The reversal of 81373486 is 68437318.

It is a semiprime because it is the product of two primes.

It is a Smith number, since the sum of its digits (40) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81373483) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 20343370 + ... + 20343373.

It is an arithmetic number, because the mean of its divisors is an integer number (30515058).

Almost surely, 2^81373486 is an apocalyptic number.

81373486 is a deficient number, since it is larger than the sum of its proper divisors (40686746).

81373486 is a wasteful number, since it uses less digits than its factorization.

81373486 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 40686745.

The product of its digits is 96768, while the sum is 40.

The square root of 81373486 is about 9020.7253588611. The cubic root of 81373486 is about 433.3388639662.

The spelling of 81373486 in words is "eighty-one million, three hundred seventy-three thousand, four hundred eighty-six".