81630042485 has 16 divisors (see below), whose sum is σ = 103728024576. Its totient is φ = 61456781568.

The previous prime is 81630042457. The next prime is 81630042511. The reversal of 81630042485 is 58424003618.

It is a cyclic number.

It is not a de Polignac number, because 81630042485 - 2⁸ = 81630042229 is a prime.

It is a super-2 number, since 2×81630042485² (a number of 23 digits) contains 22 as substring.

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 15 ways as a sum of consecutive naturals, for example, 992612 + ... + 1071698.

It is an arithmetic number, because the mean of its divisors is an integer number (6483001536).

Almost surely, 2^81630042485 is an apocalyptic number.

81630042485 is a gapful number since it is divisible by the number (85) formed by its first and last digit.

It is an amenable number.

81630042485 is a deficient number, since it is larger than the sum of its proper divisors (22097982091).

81630042485 is a wasteful number, since it uses less digits than its factorization.

81630042485 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 91252.

The product of its (nonzero) digits is 184320, while the sum is 41.

The spelling of 81630042485 in words is "eighty-one billion, six hundred thirty million, forty-two thousand, four hundred eighty-five".