91068421 has 16 divisors (see below), whose sum is σ = 97187328. Its totient is φ = 85190400.

The previous prime is 91068403. The next prime is 91068427. The reversal of 91068421 is 12486019.

It is a happy number.

It is a cyclic number.

It is not a de Polignac number, because 91068421 - 2⁹ = 91067909 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (31).

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (91068427) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 173866 + ... + 174388.

It is an arithmetic number, because the mean of its divisors is an integer number (6074208).

Almost surely, 2^91068421 is an apocalyptic number.

It is an amenable number.

91068421 is a deficient number, since it is larger than the sum of its proper divisors (6118907).

91068421 is a wasteful number, since it uses less digits than its factorization.

91068421 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 732.

The product of its (nonzero) digits is 3456, while the sum is 31.

The square root of 91068421 is about 9542.9775751597. The cubic root of 91068421 is about 449.9068465615.

The spelling of 91068421 in words is "ninety-one million, sixty-eight thousand, four hundred twenty-one".