81902075 has 6 divisors (see below), whose sum is σ = 101558604. Its totient is φ = 65521640.

The previous prime is 81902071. The next prime is 81902083. The reversal of 81902075 is 57020918.

It is not a de Polignac number, because 81902075 - 2² = 81902071 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (81902071) 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 5 ways as a sum of consecutive naturals, for example, 1638017 + ... + 1638066.

It is an arithmetic number, because the mean of its divisors is an integer number (16926434).

Almost surely, 2^81902075 is an apocalyptic number.

81902075 is a deficient number, since it is larger than the sum of its proper divisors (19656529).

81902075 is a wasteful number, since it uses less digits than its factorization.

81902075 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3276093 (or 3276088 counting only the distinct ones).

The product of its (nonzero) digits is 5040, while the sum is 32.

The square root of 81902075 is about 9049.9765193066. The cubic root of 81902075 is about 434.2751393030.

The spelling of 81902075 in words is "eighty-one million, nine hundred two thousand, seventy-five".