81873153 has 16 divisors (see below), whose sum is σ = 123004800. Its totient is φ = 53812080.

The previous prime is 81873137. The next prime is 81873203. The reversal of 81873153 is 35137818.

It is not a de Polignac number, because 81873153 - 2⁴ = 81873137 is a prime.

It is a super-2 number, since 2×81873153² = 13406426364322818, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (81873053) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 19438 + ... + 23271.

It is an arithmetic number, because the mean of its divisors is an integer number (7687800).

Almost surely, 2^81873153 is an apocalyptic number.

It is an amenable number.

81873153 is a deficient number, since it is larger than the sum of its proper divisors (41131647).

81873153 is a wasteful number, since it uses less digits than its factorization.

81873153 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 42789 (or 42783 counting only the distinct ones).

The product of its digits is 20160, while the sum is 36.

The square root of 81873153 is about 9048.3784735167. The cubic root of 81873153 is about 434.2240148989.

The spelling of 81873153 in words is "eighty-one million, eight hundred seventy-three thousand, one hundred fifty-three".