81486757 has 4 divisors (see below), whose sum is σ = 88894656. Its totient is φ = 74078860.

The previous prime is 81486751. The next prime is 81486793. The reversal of 81486757 is 75768418.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 81486757 - 2¹⁵ = 81453989 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81486751) 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, 3703933 + ... + 3703954.

It is an arithmetic number, because the mean of its divisors is an integer number (22223664).

Almost surely, 2^81486757 is an apocalyptic number.

It is an amenable number.

81486757 is a deficient number, since it is larger than the sum of its proper divisors (7407899).

81486757 is a wasteful number, since it uses less digits than its factorization.

81486757 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7407898.

The product of its digits is 376320, while the sum is 46.

The square root of 81486757 is about 9027.0015509027. The cubic root of 81486757 is about 433.5398383922.

It can be divided in two parts, 814 and 86757, that added together give a triangular number (87571 = T₄₁₈).

The spelling of 81486757 in words is "eighty-one million, four hundred eighty-six thousand, seven hundred fifty-seven".