81238516 has 12 divisors (see below), whose sum is σ = 144577440. Its totient is φ = 39930680.

The previous prime is 81238501. The next prime is 81238523. The reversal of 81238516 is 61583218.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 171880 + ... + 172351.

It is an arithmetic number, because the mean of its divisors is an integer number (12048120).

Almost surely, 2^81238516 is an apocalyptic number.

It is an amenable number.

81238516 is a deficient number, since it is larger than the sum of its proper divisors (63338924).

81238516 is a wasteful number, since it uses less digits than its factorization.

81238516 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 344294 (or 344292 counting only the distinct ones).

The product of its digits is 11520, while the sum is 34.

The square root of 81238516 is about 9013.2411484438. The cubic root of 81238516 is about 433.0991457810.

The spelling of 81238516 in words is "eighty-one million, two hundred thirty-eight thousand, five hundred sixteen".