81006554 has 8 divisors (see below), whose sum is σ = 122875380. Its totient is φ = 40048096.

The previous prime is 81006491. The next prime is 81006577. The reversal of 81006554 is 45560018.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 67486225 + 13520329 = 8215^2 + 3677^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 227369 + ... + 227724.

Almost surely, 2^81006554 is an apocalyptic number.

81006554 is a deficient number, since it is larger than the sum of its proper divisors (41868826).

81006554 is a wasteful number, since it uses less digits than its factorization.

81006554 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 455184.

The product of its (nonzero) digits is 4800, while the sum is 29.

The square root of 81006554 is about 9000.3641037460. The cubic root of 81006554 is about 432.6865405351.

The spelling of 81006554 in words is "eighty-one million, six thousand, five hundred fifty-four".