91669121 has 4 divisors (see below), whose sum is σ = 92284500. Its totient is φ = 91053744.

The previous prime is 91669057. The next prime is 91669133. The reversal of 91669121 is 12196619.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 18395521 + 73273600 = 4289^2 + 8560^2 .

It is a cyclic number.

It is not a de Polignac number, because 91669121 - 2⁶ = 91669057 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (91669141) 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, 307466 + ... + 307763.

It is an arithmetic number, because the mean of its divisors is an integer number (23071125).

Almost surely, 2^91669121 is an apocalyptic number.

It is an amenable number.

91669121 is a deficient number, since it is larger than the sum of its proper divisors (615379).

91669121 is a wasteful number, since it uses less digits than its factorization.

91669121 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 615378.

The product of its digits is 5832, while the sum is 35.

The square root of 91669121 is about 9574.3992500835. The cubic root of 91669121 is about 450.8938955871.

The spelling of 91669121 in words is "ninety-one million, six hundred sixty-nine thousand, one hundred twenty-one".