81152923 has 4 divisors (see below), whose sum is σ = 81191808. Its totient is φ = 81114040.

The previous prime is 81152893. The next prime is 81152927. The reversal of 81152923 is 32925118.

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 81152923 - 2¹³ = 81144731 is a prime.

It is a super-2 number, since 2×81152923² = 13171593822887858, 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 a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (81152927) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 16123 + ... + 20548.

It is an arithmetic number, because the mean of its divisors is an integer number (20297952).

Almost surely, 2^81152923 is an apocalyptic number.

81152923 is a deficient number, since it is larger than the sum of its proper divisors (38885).

81152923 is a wasteful number, since it uses less digits than its factorization.

81152923 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 38884.

The product of its digits is 4320, while the sum is 31.

The square root of 81152923 is about 9008.4917161532. The cubic root of 81152923 is about 432.9469877336.

The spelling of 81152923 in words is "eighty-one million, one hundred fifty-two thousand, nine hundred twenty-three".