90781893 has 12 divisors (see below), whose sum is σ = 131309100. Its totient is φ = 60438336.

The previous prime is 90781879. The next prime is 90781907. The reversal of 90781893 is 39818709.

It is an interprime number because it is at equal distance from previous prime (90781879) and next prime (90781907).

It can be written as a sum of positive squares in 2 ways, for example, as 25220484 + 65561409 = 5022^2 + 8097^2 .

It is not a de Polignac number, because 90781893 - 2⁴ = 90781877 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (90781843) 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, 433 + ... + 13481.

It is an arithmetic number, because the mean of its divisors is an integer number (10942425).

Almost surely, 2^90781893 is an apocalyptic number.

It is an amenable number.

90781893 is a deficient number, since it is larger than the sum of its proper divisors (40527207).

90781893 is a wasteful number, since it uses less digits than its factorization.

90781893 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 13828 (or 13825 counting only the distinct ones).

The product of its (nonzero) digits is 108864, while the sum is 45.

The square root of 90781893 is about 9527.9532429583. The cubic root of 90781893 is about 449.4345044787.

The spelling of 90781893 in words is "ninety million, seven hundred eighty-one thousand, eight hundred ninety-three".