90439439 has 4 divisors (see below), whose sum is σ = 95759424. Its totient is φ = 85119456.

The previous prime is 90439423. The next prime is 90439451. The reversal of 90439439 is 93493409.

It is a happy number.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 93493409 = 103 ⋅907703.

It is a cyclic number.

It is not a de Polignac number, because 90439439 - 2⁴ = 90439423 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 90439396 and 90439405.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (90439499) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2659967 + ... + 2660000.

It is an arithmetic number, because the mean of its divisors is an integer number (23939856).

Almost surely, 2^90439439 is an apocalyptic number.

90439439 is a deficient number, since it is larger than the sum of its proper divisors (5319985).

90439439 is a wasteful number, since it uses less digits than its factorization.

90439439 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5319984.

The product of its (nonzero) digits is 104976, while the sum is 41.

The square root of 90439439 is about 9509.9652470448. The cubic root of 90439439 is about 448.8686626343.

The spelling of 90439439 in words is "ninety million, four hundred thirty-nine thousand, four hundred thirty-nine".