81744400134 has 48 divisors (see below), whose sum is σ = 179885815200. Its totient is φ = 26824203648.

The previous prime is 81744400103. The next prime is 81744400187. The reversal of 81744400134 is 43100444718.

It is a happy number.

81744400134 is a `hidden beast` number, since 81 + 7 + 4 + 440 + 0 + 134 = 666.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 255447 + ... + 478269.

It is an arithmetic number, because the mean of its divisors is an integer number (3747621150).

Almost surely, 2^81744400134 is an apocalyptic number.

81744400134 is an abundant number, since it is smaller than the sum of its proper divisors (98141415066).

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

81744400134 is a wasteful number, since it uses less digits than its factorization.

81744400134 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 223149 (or 223146 counting only the distinct ones).

The product of its (nonzero) digits is 43008, while the sum is 36.

The spelling of 81744400134 in words is "eighty-one billion, seven hundred forty-four million, four hundred thousand, one hundred thirty-four".