81074489 has 4 divisors (see below), whose sum is σ = 82284624. Its totient is φ = 79864356.

The previous prime is 81074453. The next prime is 81074491. The reversal of 81074489 is 98447018.

It is a happy number.

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.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-81074489 is a prime.

It is a super-2 number, since 2×81074489² = 13146145533222242, which contains 22 as substring.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (81074419) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 604967 + ... + 605100.

It is an arithmetic number, because the mean of its divisors is an integer number (20571156).

Almost surely, 2^81074489 is an apocalyptic number.

It is an amenable number.

81074489 is a deficient number, since it is larger than the sum of its proper divisors (1210135).

81074489 is a wasteful number, since it uses less digits than its factorization.

81074489 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1210134.

The product of its (nonzero) digits is 64512, while the sum is 41.

The square root of 81074489 is about 9004.1373268070. The cubic root of 81074489 is about 432.8074622194.

The spelling of 81074489 in words is "eighty-one million, seventy-four thousand, four hundred eighty-nine".