91397090 has 8 divisors (see below), whose sum is σ = 164514780. Its totient is φ = 36558832.

The previous prime is 91397063. The next prime is 91397099. The reversal of 91397090 is 9079319.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 83740801 + 7656289 = 9151^2 + 2767^2 .

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

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (91397099) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 4569845 + ... + 4569864.

Almost surely, 2^91397090 is an apocalyptic number.

91397090 is a deficient number, since it is larger than the sum of its proper divisors (73117690).

91397090 is a wasteful number, since it uses less digits than its factorization.

91397090 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9139716.

The product of its (nonzero) digits is 15309, while the sum is 38.

The square root of 91397090 is about 9560.1825296382. The cubic root of 91397090 is about 450.4474397322.

The spelling of 91397090 in words is "ninety-one million, three hundred ninety-seven thousand, ninety".