81418763 has 4 divisors (see below), whose sum is σ = 86208120. Its totient is φ = 76629408.

The previous prime is 81418709. The next prime is 81418807. The reversal of 81418763 is 36781418.

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

It is a cyclic number.

It is not a de Polignac number, because 81418763 - 2⁶ = 81418699 is a prime.

It is an alternating number because its digits alternate between even and odd.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (81498763) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2394653 + ... + 2394686.

It is an arithmetic number, because the mean of its divisors is an integer number (21552030).

Almost surely, 2^81418763 is an apocalyptic number.

81418763 is a deficient number, since it is larger than the sum of its proper divisors (4789357).

81418763 is a wasteful number, since it uses less digits than its factorization.

81418763 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4789356.

The product of its digits is 32256, while the sum is 38.

The square root of 81418763 is about 9023.2346195807. The cubic root of 81418763 is about 433.4192203856.

The spelling of 81418763 in words is "eighty-one million, four hundred eighteen thousand, seven hundred sixty-three".