81363123 has 10 divisors (see below), whose sum is σ = 121542564. Its totient is φ = 54242028.

The previous prime is 81363103. The next prime is 81363133. The reversal of 81363123 is 32136318.

It is a happy number.

81363123 is a `hidden beast` number, since 8 + 1 + 3 + 631 + 23 = 666.

It is not a de Polignac number, because 81363123 - 2⁶ = 81363059 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is not an unprimeable number, because it can be changed into a prime (81363103) by changing a digit.

It is a polite number, since it can be written in 9 ways as a sum of consecutive naturals, for example, 502161 + ... + 502322.

Almost surely, 2^81363123 is an apocalyptic number.

81363123 is a deficient number, since it is larger than the sum of its proper divisors (40179441).

81363123 is a wasteful number, since it uses less digits than its factorization.

81363123 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1004495 (or 1004486 counting only the distinct ones).

The product of its digits is 2592, while the sum is 27.

The square root of 81363123 is about 9020.1509410874. The cubic root of 81363123 is about 433.3204677969.

It can be divided in two parts, 813 and 63123, that added together give a palindrome (63936).

The spelling of 81363123 in words is "eighty-one million, three hundred sixty-three thousand, one hundred twenty-three".