81237078 has 24 divisors (see below), whose sum is σ = 189553728. Its totient is φ = 24995952.

The previous prime is 81237073. The next prime is 81237083. The reversal of 81237078 is 87073218.

It is an interprime number because it is at equal distance from previous prime (81237073) and next prime (81237083).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81237071) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 173350 + ... + 173817.

It is an arithmetic number, because the mean of its divisors is an integer number (7898072).

Almost surely, 2^81237078 is an apocalyptic number.

81237078 is an abundant number, since it is smaller than the sum of its proper divisors (108316650).

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

81237078 is a wasteful number, since it uses less digits than its factorization.

81237078 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 347188 (or 347185 counting only the distinct ones).

The product of its (nonzero) digits is 18816, while the sum is 36.

The square root of 81237078 is about 9013.1613765648. The cubic root of 81237078 is about 433.0965903419.

The spelling of 81237078 in words is "eighty-one million, two hundred thirty-seven thousand, seventy-eight".