90243987 has 8 divisors (see below), whose sum is σ = 121973904. Its totient is φ = 59338368.

The previous prime is 90243931. The next prime is 90244003. The reversal of 90243987 is 78934209.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 90243987 - 2⁷ = 90243859 is a prime.

It is not an unprimeable number, because it can be changed into a prime (90243917) 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, 205818 + ... + 206255.

It is an arithmetic number, because the mean of its divisors is an integer number (15246738).

Almost surely, 2^90243987 is an apocalyptic number.

90243987 is a deficient number, since it is larger than the sum of its proper divisors (31729917).

90243987 is a wasteful number, since it uses less digits than its factorization.

90243987 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 412149.

The product of its (nonzero) digits is 108864, while the sum is 42.

The square root of 90243987 is about 9499.6835210443. The cubic root of 90243987 is about 448.5450738869.

The spelling of 90243987 in words is "ninety million, two hundred forty-three thousand, nine hundred eighty-seven".