81893153 has 2 divisors, whose sum is σ = 81893154. Its totient is φ = 81893152.

The previous prime is 81893143. The next prime is 81893159. The reversal of 81893153 is 35139818.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 81848209 + 44944 = 9047^2 + 212^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-81893153 is a prime.

It is equal to p_4773539 and since 81893153 and 4773539 have the same sum of digits, it is a Honaker prime.

It is not a weakly prime, because it can be changed into another prime (81893159) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 40946576 + 40946577.

It is an arithmetic number, because the mean of its divisors is an integer number (40946577).

Almost surely, 2^81893153 is an apocalyptic number.

It is an amenable number.

81893153 is a deficient number, since it is larger than the sum of its proper divisors (1).

81893153 is an equidigital number, since it uses as much as digits as its factorization.

81893153 is an evil number, because the sum of its binary digits is even.

The product of its digits is 25920, while the sum is 38.

The square root of 81893153 is about 9049.4835764258. The cubic root of 81893153 is about 434.2593694807.

The spelling of 81893153 in words is "eighty-one million, eight hundred ninety-three thousand, one hundred fifty-three".