81662853 has 12 divisors (see below), whose sum is σ = 110450240. Its totient is φ = 53661192.

The previous prime is 81662839. The next prime is 81662879. The reversal of 81662853 is 35826618.

It is a happy number.

It is not a de Polignac number, because 81662853 - 2⁵ = 81662821 is a prime.

It is a hoax number, since the sum of its digits (39) coincides with the sum of the digits of its distinct prime factors.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81662653) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 138826 + ... + 139412.

Almost surely, 2^81662853 is an apocalyptic number.

It is an amenable number.

81662853 is a deficient number, since it is larger than the sum of its proper divisors (28787387).

81662853 is an frugal number, since it uses more digits than its factorization.

81662853 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1256 (or 669 counting only the distinct ones).

The product of its digits is 69120, while the sum is 39.

The square root of 81662853 is about 9036.7501348660. The cubic root of 81662853 is about 433.8519124255.

The spelling of 81662853 in words is "eighty-one million, six hundred sixty-two thousand, eight hundred fifty-three".