81942624 has 48 divisors (see below), whose sum is σ = 239001840. Its totient is φ = 27313920.

The previous prime is 81942617. The next prime is 81942673. The reversal of 81942624 is 42624918.

It is a tau number, because it is divible by the number of its divisors (48).

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a nude number because it is divisible by every one of its digits.

It is a congruent number.

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, 46557 + ... + 48284.

It is an arithmetic number, because the mean of its divisors is an integer number (4979205).

Almost surely, 2^81942624 is an apocalyptic number.

It is an amenable number.

81942624 is an abundant number, since it is smaller than the sum of its proper divisors (157059216).

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

81942624 is a wasteful number, since it uses less digits than its factorization.

81942624 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 94860 (or 94846 counting only the distinct ones).

The product of its digits is 27648, while the sum is 36.

The square root of 81942624 is about 9052.2165241448. The cubic root of 81942624 is about 434.3467960847.

The spelling of 81942624 in words is "eighty-one million, nine hundred forty-two thousand, six hundred twenty-four".