81302458 has 4 divisors (see below), whose sum is σ = 121953690. Its totient is φ = 40651228.

The previous prime is 81302453. The next prime is 81302497. The reversal of 81302458 is 85420318.

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

It can be written as a sum of positive squares in only one way, i.e., 43072969 + 38229489 = 6563^2 + 6183^2 .

It is a super-2 number, since 2×81302458² = 13220179353683528, which contains 22 as substring.

It is a Smith number, since the sum of its digits (31) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is not an unprimeable number, because it can be changed into a prime (81302453) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 20325613 + ... + 20325616.

Almost surely, 2^81302458 is an apocalyptic number.

81302458 is a deficient number, since it is larger than the sum of its proper divisors (40651232).

81302458 is a wasteful number, since it uses less digits than its factorization.

81302458 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 40651231.

The product of its (nonzero) digits is 7680, while the sum is 31.

The square root of 81302458 is about 9016.7875654248. The cubic root of 81302458 is about 433.2127452756.

The spelling of 81302458 in words is "eighty-one million, three hundred two thousand, four hundred fifty-eight".