81923272 has 16 divisors (see below), whose sum is σ = 162642060. Its totient is φ = 38552064.

The previous prime is 81923267. The next prime is 81923293. The reversal of 81923272 is 27232918.

It can be written as a sum of positive squares in 2 ways, for example, as 76842756 + 5080516 = 8766^2 + 2254^2 .

It is a super-2 number, since 2×81923272² = 13422844990371968, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (34).

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 301053 + ... + 301324.

Almost surely, 2^81923272 is an apocalyptic number.

It is an amenable number.

81923272 is a deficient number, since it is larger than the sum of its proper divisors (80718788).

81923272 is a wasteful number, since it uses less digits than its factorization.

81923272 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 602400 (or 602396 counting only the distinct ones).

The product of its digits is 12096, while the sum is 34.

The square root of 81923272 is about 9051.1475515539. The cubic root of 81923272 is about 434.3126008532.

The spelling of 81923272 in words is "eighty-one million, nine hundred twenty-three thousand, two hundred seventy-two".