81544842 has 24 divisors (see below), whose sum is σ = 176847840. Its totient is φ = 27155880.

The previous prime is 81544823. The next prime is 81544843. The reversal of 81544842 is 24844518.

It is a super-2 number, since 2×81544842² = 13299122513609928, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 81544797 and 81544806.

It is not an unprimeable number, because it can be changed into a prime (81544843) 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, 32617 + ... + 35027.

It is an arithmetic number, because the mean of its divisors is an integer number (7368660).

Almost surely, 2^81544842 is an apocalyptic number.

81544842 is an abundant number, since it is smaller than the sum of its proper divisors (95302998).

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

81544842 is a wasteful number, since it uses less digits than its factorization.

81544842 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4298 (or 4295 counting only the distinct ones).

The product of its digits is 40960, while the sum is 36.

The square root of 81544842 is about 9030.2182697873. The cubic root of 81544842 is about 433.6428251899.

It can be divided in two parts, 8154 and 4842, that added together give a square (12996 = 114²).

The spelling of 81544842 in words is "eighty-one million, five hundred forty-four thousand, eight hundred forty-two".