81738862 has 4 divisors (see below), whose sum is σ = 122608296. Its totient is φ = 40869430.

The previous prime is 81738823. The next prime is 81738863. The reversal of 81738862 is 26883718.

It is a happy number.

It is a semiprime because it is the product of two primes.

It is a super-2 number, since 2×81738862² = 13362483122110088, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81738863) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 20434714 + ... + 20434717.

It is an arithmetic number, because the mean of its divisors is an integer number (30652074).

Almost surely, 2^81738862 is an apocalyptic number.

81738862 is a deficient number, since it is larger than the sum of its proper divisors (40869434).

81738862 is a wasteful number, since it uses less digits than its factorization.

81738862 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 40869433.

The product of its digits is 129024, while the sum is 43.

The square root of 81738862 is about 9040.9547062243. The cubic root of 81738862 is about 433.9864755425.

The spelling of 81738862 in words is "eighty-one million, seven hundred thirty-eight thousand, eight hundred sixty-two".