81062556444 has 36 divisors (see below), whose sum is σ = 204924832840. Its totient is φ = 27018649440.

The previous prime is 81062556439. The next prime is 81062556457. The reversal of 81062556444 is 44465526018.

It is a happy number.

81062556444 is a `hidden beast` number, since 8 + 10 + 625 + 5 + 6 + 4 + 4 + 4 = 666.

It is a tau number, because it is divible by the number of its divisors (36).

It is a super-2 number, since 2×81062556444² (a number of 23 digits) contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 81062556444.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 390714 + ... + 561054.

Almost surely, 2^81062556444 is an apocalyptic number.

It is an amenable number.

81062556444 is an abundant number, since it is smaller than the sum of its proper divisors (123862276396).

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

81062556444 is a wasteful number, since it uses less digits than its factorization.

81062556444 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 183570 (or 183565 counting only the distinct ones).

The product of its (nonzero) digits is 921600, while the sum is 45.

The spelling of 81062556444 in words is "eighty-one billion, sixty-two million, five hundred fifty-six thousand, four hundred forty-four".