68390090 has 16 divisors (see below), whose sum is σ = 123425640. Its totient is φ = 27284160.

The previous prime is 68390059. The next prime is 68390093. The reversal of 68390090 is 9009386.

It can be written as a sum of positive squares in 4 ways, for example, as 37908649 + 30481441 = 6157^2 + 5521^2 .

It is a self number, because there is not a number n which added to its sum of digits gives 68390090.

It is not an unprimeable number, because it can be changed into a prime (68390093) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 4901 + ... + 12680.

Almost surely, 2^68390090 is an apocalyptic number.

68390090 is a deficient number, since it is larger than the sum of its proper divisors (55035550).

68390090 is a wasteful number, since it uses less digits than its factorization.

68390090 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 17977.

The product of its (nonzero) digits is 11664, while the sum is 35.

The square root of 68390090 is about 8269.8301070820. The cubic root of 68390090 is about 408.9445189497.

The spelling of 68390090 in words is "sixty-eight million, three hundred ninety thousand, ninety".