81963458 has 4 divisors (see below), whose sum is σ = 122945190. Its totient is φ = 40981728.

The previous prime is 81963457. The next prime is 81963463. The reversal of 81963458 is 85436918.

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., 75394489 + 6568969 = 8683^2 + 2563^2 .

It is not an unprimeable number, because it can be changed into a prime (81963457) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 20490863 + ... + 20490866.

Almost surely, 2^81963458 is an apocalyptic number.

81963458 is a deficient number, since it is larger than the sum of its proper divisors (40981732).

81963458 is a wasteful number, since it uses less digits than its factorization.

81963458 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 40981731.

The product of its digits is 207360, while the sum is 44.

The square root of 81963458 is about 9053.3672188860. The cubic root of 81963458 is about 434.3836040116.

The spelling of 81963458 in words is "eighty-one million, nine hundred sixty-three thousand, four hundred fifty-eight".