91522821 has 8 divisors (see below), whose sum is σ = 131417440. Its totient is φ = 56321712.

The previous prime is 91522817. The next prime is 91522841. The reversal of 91522821 is 12822519.

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

It is not a de Polignac number, because 91522821 - 2² = 91522817 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (91522841) 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, 1173331 + ... + 1173408.

It is an arithmetic number, because the mean of its divisors is an integer number (16427180).

Almost surely, 2^91522821 is an apocalyptic number.

It is an amenable number.

91522821 is a deficient number, since it is larger than the sum of its proper divisors (39894619).

91522821 is a wasteful number, since it uses less digits than its factorization.

91522821 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2346755.

The product of its digits is 2880, while the sum is 30.

The square root of 91522821 is about 9566.7560332644. The cubic root of 91522821 is about 450.6538987368.

The spelling of 91522821 in words is "ninety-one million, five hundred twenty-two thousand, eight hundred twenty-one".