81542374292 has 24 divisors (see below), whose sum is σ = 146232071496. Its totient is φ = 39770676608.

The previous prime is 81542374289. The next prime is 81542374297. The reversal of 81542374292 is 29247324518.

It can be written as a sum of positive squares in 4 ways, for example, as 14048412676 + 67493961616 = 118526^2 + 259796^2 .

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81542374297) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1074983 + ... + 1148334.

It is an arithmetic number, because the mean of its divisors is an integer number (6093002979).

Almost surely, 2^81542374292 is an apocalyptic number.

It is an amenable number.

81542374292 is a deficient number, since it is larger than the sum of its proper divisors (64689697204).

81542374292 is a wasteful number, since it uses less digits than its factorization.

81542374292 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2223547 (or 2223545 counting only the distinct ones).

The product of its digits is 967680, while the sum is 47.

The spelling of 81542374292 in words is "eighty-one billion, five hundred forty-two million, three hundred seventy-four thousand, two hundred ninety-two".