81000542 has 16 divisors (see below), whose sum is σ = 139032960. Its totient is φ = 34670808.

The previous prime is 81000541. The next prime is 81000571. The reversal of 81000542 is 24500018.

It is a super-2 number, since 2×81000542² = 13122175608587528, which contains 22 as substring.

It is a nialpdrome in base 14.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81000541) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 9509 + ... + 15887.

It is an arithmetic number, because the mean of its divisors is an integer number (8689560).

Almost surely, 2^81000542 is an apocalyptic number.

81000542 is a deficient number, since it is larger than the sum of its proper divisors (58032418).

81000542 is a wasteful number, since it uses less digits than its factorization.

81000542 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7295.

The product of its (nonzero) digits is 320, while the sum is 20.

The square root of 81000542 is about 9000.0301110607. The cubic root of 81000542 is about 432.6758361509.

The spelling of 81000542 in words is "eighty-one million, five hundred forty-two", and thus it is an aban number.