90439638 has 16 divisors (see below), whose sum is σ = 182078976. Its totient is φ = 29946600.

The previous prime is 90439631. The next prime is 90439667. The reversal of 90439638 is 83693409.

It is a self number, because there is not a number n which added to its sum of digits gives 90439638.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (90439631) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 49006 + ... + 50817.

It is an arithmetic number, because the mean of its divisors is an integer number (11379936).

Almost surely, 2^90439638 is an apocalyptic number.

90439638 is an abundant number, since it is smaller than the sum of its proper divisors (91639338).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

90439638 is a wasteful number, since it uses less digits than its factorization.

90439638 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 99979.

The product of its (nonzero) digits is 139968, while the sum is 42.

The square root of 90439638 is about 9509.9757097482. The cubic root of 90439638 is about 448.8689918593.

It can be divided in two parts, 9043 and 9638, that added together give a palindrome (18681).

The spelling of 90439638 in words is "ninety million, four hundred thirty-nine thousand, six hundred thirty-eight".