81459690 has 48 divisors (see below), whose sum is σ = 211711968. Its totient is φ = 20050368.

The previous prime is 81459683. The next prime is 81459691. The reversal of 81459690 is 9695418.

It is a super-2 number, since 2×81459690² = 13271362189792200, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (81459691) by changing a digit.

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 23 ways as a sum of consecutive naturals, for example, 2964 + ... + 13103.

It is an arithmetic number, because the mean of its divisors is an integer number (4410666).

Almost surely, 2^81459690 is an apocalyptic number.

81459690 is an abundant number, since it is smaller than the sum of its proper divisors (130252278).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

81459690 is a wasteful number, since it uses less digits than its factorization.

81459690 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 16103 (or 16090 counting only the distinct ones).

The product of its (nonzero) digits is 77760, while the sum is 42.

The square root of 81459690 is about 9025.5022020938. The cubic root of 81459690 is about 433.4918309092.

The spelling of 81459690 in words is "eighty-one million, four hundred fifty-nine thousand, six hundred ninety".