81354142 has 4 divisors (see below), whose sum is σ = 122031216. Its totient is φ = 40677070.

The previous prime is 81354113. The next prime is 81354167. The reversal of 81354142 is 24145318.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 24145318 = 2 ⋅12072659.

It is a self number, because there is not a number n which added to its sum of digits gives 81354142.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 20338534 + ... + 20338537.

It is an arithmetic number, because the mean of its divisors is an integer number (30507804).

Almost surely, 2^81354142 is an apocalyptic number.

81354142 is a deficient number, since it is larger than the sum of its proper divisors (40677074).

81354142 is a wasteful number, since it uses less digits than its factorization.

81354142 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 40677073.

The product of its digits is 3840, while the sum is 28.

The square root of 81354142 is about 9019.6530975421. The cubic root of 81354142 is about 433.3045236599.

The spelling of 81354142 in words is "eighty-one million, three hundred fifty-four thousand, one hundred forty-two".