81677160 has 112 divisors (see below), whose sum is σ = 275632740. Its totient is φ = 21772800.

The previous prime is 81677159. The next prime is 81677161. The reversal of 81677160 is 6177618.

It is a happy number.

It is an interprime number because it is at equal distance from previous prime (81677159) and next prime (81677161).

It can be written as a sum of positive squares in 2 ways, for example, as 81324324 + 352836 = 9018^2 + 594^2 .

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81677161) by changing a digit.

It is a polite number, since it can be written in 27 ways as a sum of consecutive naturals, for example, 27760 + ... + 30560.

Almost surely, 2^81677160 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 81677160, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (137816370).

81677160 is an abundant number, since it is smaller than the sum of its proper divisors (193955580).

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

81677160 is a wasteful number, since it uses less digits than its factorization.

81677160 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2830 (or 2811 counting only the distinct ones).

The product of its (nonzero) digits is 14112, while the sum is 36.

The square root of 81677160 is about 9037.5417011486. The cubic root of 81677160 is about 433.8772473101.

The spelling of 81677160 in words is "eighty-one million, six hundred seventy-seven thousand, one hundred sixty".