81643155294 has 16 divisors (see below), whose sum is σ = 163368100368. Its totient is φ = 27200753472.

The previous prime is 81643155281. The next prime is 81643155337. The reversal of 81643155294 is 49255134618.

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, 3394927 + ... + 3418890.

It is an arithmetic number, because the mean of its divisors is an integer number (10210506273).

Almost surely, 2^81643155294 is an apocalyptic number.

81643155294 is an abundant number, since it is smaller than the sum of its proper divisors (81724945074).

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

81643155294 is a wasteful number, since it uses less digits than its factorization.

81643155294 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6815819.

The product of its digits is 1036800, while the sum is 48.

The spelling of 81643155294 in words is "eighty-one billion, six hundred forty-three million, one hundred fifty-five thousand, two hundred ninety-four".