81240884 has 36 divisors (see below), whose sum is σ = 151570944. Its totient is φ = 38093328.

The previous prime is 81240883. The next prime is 81240893. The reversal of 81240884 is 48804218.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81240881) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 183167 + ... + 183609.

It is an arithmetic number, because the mean of its divisors is an integer number (4210304).

Almost surely, 2^81240884 is an apocalyptic number.

It is an amenable number.

81240884 is a deficient number, since it is larger than the sum of its proper divisors (70330060).

81240884 is a wasteful number, since it uses less digits than its factorization.

81240884 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 612 (or 591 counting only the distinct ones).

The product of its (nonzero) digits is 16384, while the sum is 35.

The square root of 81240884 is about 9013.3725097768. The cubic root of 81240884 is about 433.1033538376.

The spelling of 81240884 in words is "eighty-one million, two hundred forty thousand, eight hundred eighty-four".