81630455 has 8 divisors (see below), whose sum is σ = 99418992. Its totient is φ = 64329408.

The previous prime is 81630433. The next prime is 81630509. The reversal of 81630455 is 55403618.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 81630455 - 2¹⁶ = 81564919 is a prime.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 121502 + ... + 122171.

It is an arithmetic number, because the mean of its divisors is an integer number (12427374).

Almost surely, 2^81630455 is an apocalyptic number.

81630455 is a deficient number, since it is larger than the sum of its proper divisors (17788537).

81630455 is a wasteful number, since it uses less digits than its factorization.

81630455 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 243745.

The product of its (nonzero) digits is 14400, while the sum is 32.

The square root of 81630455 is about 9034.9573878353. The cubic root of 81630455 is about 433.7945309971.

The spelling of 81630455 in words is "eighty-one million, six hundred thirty thousand, four hundred fifty-five".