81254947668 has 24 divisors (see below), whose sum is σ = 200747518272. Its totient is φ = 25491748224.

The previous prime is 81254947603. The next prime is 81254947687. The reversal of 81254947668 is 86674945218.

It is a happy number.

It is a super-3 number, since 3×81254947668³ (a number of 34 digits) contains 333 as substring.

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, 199154080 + ... + 199154487.

It is an arithmetic number, because the mean of its divisors is an integer number (8364479928).

Almost surely, 2^81254947668 is an apocalyptic number.

It is an amenable number.

81254947668 is an abundant number, since it is smaller than the sum of its proper divisors (119492570604).

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

81254947668 is a wasteful number, since it uses less digits than its factorization.

81254947668 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 398308591 (or 398308589 counting only the distinct ones).

The product of its digits is 23224320, while the sum is 60.

The spelling of 81254947668 in words is "eighty-one billion, two hundred fifty-four million, nine hundred forty-seven thousand, six hundred sixty-eight".