90709639 has 2 divisors, whose sum is σ = 90709640. Its totient is φ = 90709638.

The previous prime is 90709583. The next prime is 90709649. The reversal of 90709639 is 93690709.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 90709639 - 2¹³ = 90701447 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 90709595 and 90709604.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (90709649) 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 as a sum of consecutive naturals, namely, 45354819 + 45354820.

It is an arithmetic number, because the mean of its divisors is an integer number (45354820).

Almost surely, 2^90709639 is an apocalyptic number.

90709639 is a deficient number, since it is larger than the sum of its proper divisors (1).

90709639 is an equidigital number, since it uses as much as digits as its factorization.

90709639 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 91854, while the sum is 43.

The square root of 90709639 is about 9524.1608029264. The cubic root of 90709639 is about 449.3152367162.

The spelling of 90709639 in words is "ninety million, seven hundred nine thousand, six hundred thirty-nine".