81542384 has 80 divisors (see below), whose sum is σ = 198963456. Its totient is φ = 31711680.

The previous prime is 81542381. The next prime is 81542393. The reversal of 81542384 is 48324518.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81542381) 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, 148799 + ... + 149345.

Almost surely, 2^81542384 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 81542384, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (99481728).

81542384 is an abundant number, since it is smaller than the sum of its proper divisors (117421072).

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

81542384 is a wasteful number, since it uses less digits than its factorization.

81542384 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 595 (or 567 counting only the distinct ones).

The product of its digits is 30720, while the sum is 35.

The square root of 81542384 is about 9030.0821701688. The cubic root of 81542384 is about 433.6384680585.

The spelling of 81542384 in words is "eighty-one million, five hundred forty-two thousand, three hundred eighty-four".