81677140 has 48 divisors (see below), whose sum is σ = 179843328. Its totient is φ = 31099904.

The previous prime is 81677131. The next prime is 81677147. The reversal of 81677140 is 4177618.

It is a junction number, because it is equal to n+sod(n) for n = 81677096 and 81677105.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81677147) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 162129 + ... + 162631.

It is an arithmetic number, because the mean of its divisors is an integer number (3746736).

Almost surely, 2^81677140 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 81677140, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (89921664).

81677140 is an abundant number, since it is smaller than the sum of its proper divisors (98166188).

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

81677140 is a wasteful number, since it uses less digits than its factorization.

81677140 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 888 (or 886 counting only the distinct ones).

The product of its (nonzero) digits is 9408, while the sum is 34.

The square root of 81677140 is about 9037.5405946530. The cubic root of 81677140 is about 433.8772118961.

The spelling of 81677140 in words is "eighty-one million, six hundred seventy-seven thousand, one hundred forty".