81870260 has 24 divisors (see below), whose sum is σ = 172140360. Its totient is φ = 32707584.

The previous prime is 81870253. The next prime is 81870263. The reversal of 81870260 is 6207818.

It can be written as a sum of positive squares in 4 ways, for example, as 4218916 + 77651344 = 2054^2 + 8812^2 .

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81870263) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 18152 + ... + 22208.

It is an arithmetic number, because the mean of its divisors is an integer number (7172515).

Almost surely, 2^81870260 is an apocalyptic number.

It is an amenable number.

81870260 is an abundant number, since it is smaller than the sum of its proper divisors (90270100).

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

81870260 is a wasteful number, since it uses less digits than its factorization.

81870260 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5075 (or 5073 counting only the distinct ones).

The product of its (nonzero) digits is 5376, while the sum is 32.

The square root of 81870260 is about 9048.2186092070. The cubic root of 81870260 is about 434.2189003821.

The spelling of 81870260 in words is "eighty-one million, eight hundred seventy thousand, two hundred sixty".