81037969 has 4 divisors (see below), whose sum is σ = 81377280. Its totient is φ = 80698660.

The previous prime is 81037897. The next prime is 81037981. The reversal of 81037969 is 96973018.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 96973018 = 2 ⋅48486509.

It is a cyclic number.

It is not a de Polignac number, because 81037969 - 2⁹ = 81037457 is a prime.

It is a super-2 number, since 2×81037969² = 13134304839289922, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (81037169) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 169297 + ... + 169774.

It is an arithmetic number, because the mean of its divisors is an integer number (20344320).

Almost surely, 2^81037969 is an apocalyptic number.

It is an amenable number.

81037969 is a deficient number, since it is larger than the sum of its proper divisors (339311).

81037969 is a wasteful number, since it uses less digits than its factorization.

81037969 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 339310.

The product of its (nonzero) digits is 81648, while the sum is 43.

The square root of 81037969 is about 9002.1091417512. The cubic root of 81037969 is about 432.7424664252.

The spelling of 81037969 in words is "eighty-one million, thirty-seven thousand, nine hundred sixty-nine".