81365049 has 24 divisors (see below), whose sum is σ = 127712000. Its totient is φ = 49727520.

The previous prime is 81365041. The next prime is 81365051. The reversal of 81365049 is 94056318.

It is not a de Polignac number, because 81365049 - 2³ = 81365041 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (81365041) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 2374 + ... + 12975.

Almost surely, 2^81365049 is an apocalyptic number.

It is an amenable number.

81365049 is a deficient number, since it is larger than the sum of its proper divisors (46346951).

81365049 is a wasteful number, since it uses less digits than its factorization.

81365049 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 15405 (or 15402 counting only the distinct ones).

The product of its (nonzero) digits is 25920, while the sum is 36.

The square root of 81365049 is about 9020.2577014185. The cubic root of 81365049 is about 433.3238869078.

The spelling of 81365049 in words is "eighty-one million, three hundred sixty-five thousand, forty-nine".