90442987 has 2 divisors, whose sum is σ = 90442988. Its totient is φ = 90442986.

The previous prime is 90442981. The next prime is 90442997. The reversal of 90442987 is 78924409.

It is a weak prime.

It is an emirp because it is prime and its reverse (78924409) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 90442987 - 2¹¹ = 90440939 is a prime.

It is not a weakly prime, because it can be changed into another prime (90442981) 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, 45221493 + 45221494.

It is an arithmetic number, because the mean of its divisors is an integer number (45221494).

Almost surely, 2^90442987 is an apocalyptic number.

90442987 is a deficient number, since it is larger than the sum of its proper divisors (1).

90442987 is an equidigital number, since it uses as much as digits as its factorization.

90442987 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 145152, while the sum is 43.

The square root of 90442987 is about 9510.1517863807. The cubic root of 90442987 is about 448.8745323640.

The spelling of 90442987 in words is "ninety million, four hundred forty-two thousand, nine hundred eighty-seven".