81081577658 has 8 divisors (see below), whose sum is σ = 121623942528. Its totient is φ = 40540263484.

The previous prime is 81081577637. The next prime is 81081577663. The reversal of 81081577658 is 85677518018.

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, 27716 + ... + 403647.

It is an arithmetic number, because the mean of its divisors is an integer number (15202992816).

Almost surely, 2^81081577658 is an apocalyptic number.

81081577658 is a deficient number, since it is larger than the sum of its proper divisors (40542364870).

81081577658 is a wasteful number, since it uses less digits than its factorization.

81081577658 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 525348.

The product of its (nonzero) digits is 3763200, while the sum is 56.

The spelling of 81081577658 in words is "eighty-one billion, eighty-one million, five hundred seventy-seven thousand, six hundred fifty-eight".