91072681 has 8 divisors (see below), whose sum is σ = 109561280. Its totient is φ = 73953648.

The previous prime is 91072679. The next prime is 91072691. The reversal of 91072681 is 18627019.

It is a happy number.

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 91072681 - 2¹ = 91072679 is a prime.

It is a super-2 number, since 2×91072681² = 16588466449055522, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (91072601) 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, 342246 + ... + 342511.

It is an arithmetic number, because the mean of its divisors is an integer number (13695160).

Almost surely, 2^91072681 is an apocalyptic number.

It is an amenable number.

91072681 is a deficient number, since it is larger than the sum of its proper divisors (18488599).

91072681 is a wasteful number, since it uses less digits than its factorization.

91072681 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 684783.

The product of its (nonzero) digits is 6048, while the sum is 34.

The square root of 91072681 is about 9543.2007733255. The cubic root of 91072681 is about 449.9138617019.

The spelling of 91072681 in words is "ninety-one million, seventy-two thousand, six hundred eighty-one".