91402389 has 12 divisors (see below), whose sum is σ = 142181676. Its totient is φ = 56247552.

The previous prime is 91402379. The next prime is 91402393. The reversal of 91402389 is 98320419.

It can be written as a sum of positive squares in 2 ways, for example, as 26471025 + 64931364 = 5145^2 + 8058^2 .

It is not a de Polignac number, because 91402389 - 2⁷ = 91402261 is a prime.

It is a Smith number, since the sum of its digits (36) coincides with the sum of the digits of its prime factors.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (91402309) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 390492 + ... + 390725.

It is an arithmetic number, because the mean of its divisors is an integer number (11848473).

Almost surely, 2^91402389 is an apocalyptic number.

It is an amenable number.

91402389 is a deficient number, since it is larger than the sum of its proper divisors (50779287).

91402389 is a wasteful number, since it uses less digits than its factorization.

91402389 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 781236 (or 781233 counting only the distinct ones).

The product of its (nonzero) digits is 15552, while the sum is 36.

The square root of 91402389 is about 9560.4596646814. The cubic root of 91402389 is about 450.4561448775.

The spelling of 91402389 in words is "ninety-one million, four hundred two thousand, three hundred eighty-nine".