81547805474 has 8 divisors (see below), whose sum is σ = 122322934188. Its totient is φ = 40773494080.

The previous prime is 81547805441. The next prime is 81547805483. The reversal of 81547805474 is 47450874518.

It can be written as a sum of positive squares in 2 ways, for example, as 78760493449 + 2787312025 = 280643^2 + 52795^2 .

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

It is a Curzon number.

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, 228374 + ... + 463950.

Almost surely, 2^81547805474 is an apocalyptic number.

81547805474 is a deficient number, since it is larger than the sum of its proper divisors (40775128714).

81547805474 is a wasteful number, since it uses less digits than its factorization.

81547805474 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 408660.

The product of its (nonzero) digits is 5017600, while the sum is 53.

The spelling of 81547805474 in words is "eighty-one billion, five hundred forty-seven million, eight hundred five thousand, four hundred seventy-four".