81474409 has 8 divisors (see below), whose sum is σ = 83529792. Its totient is φ = 79438320.

The previous prime is 81474391. The next prime is 81474461. The reversal of 81474409 is 90447418.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 81474409 - 2²¹ = 79377257 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (81478409) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 3924 + ... + 13354.

It is an arithmetic number, because the mean of its divisors is an integer number (10441224).

Almost surely, 2^81474409 is an apocalyptic number.

It is an amenable number.

81474409 is a deficient number, since it is larger than the sum of its proper divisors (2055383).

81474409 is a wasteful number, since it uses less digits than its factorization.

81474409 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9647.

The product of its (nonzero) digits is 32256, while the sum is 37.

The square root of 81474409 is about 9026.3175769524. The cubic root of 81474409 is about 433.5179386360.

The spelling of 81474409 in words is "eighty-one million, four hundred seventy-four thousand, four hundred nine".