81374540 has 24 divisors (see below), whose sum is σ = 184032240. Its totient is φ = 30045888.

The previous prime is 81374539. The next prime is 81374599. The reversal of 81374540 is 4547318.

It is a junction number, because it is equal to n+sod(n) for n = 81374497 and 81374506.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 156230 + ... + 156749.

It is an arithmetic number, because the mean of its divisors is an integer number (7668010).

Almost surely, 2^81374540 is an apocalyptic number.

It is an amenable number.

81374540 is an abundant number, since it is smaller than the sum of its proper divisors (102657700).

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

81374540 is a wasteful number, since it uses less digits than its factorization.

81374540 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 313001 (or 312999 counting only the distinct ones).

The product of its (nonzero) digits is 13440, while the sum is 32.

The square root of 81374540 is about 9020.7837796945. The cubic root of 81374540 is about 433.3407349163.

The spelling of 81374540 in words is "eighty-one million, three hundred seventy-four thousand, five hundred forty".