90243991870 has 32 divisors (see below), whose sum is σ = 173697379776. Its totient is φ = 33637824000.

The previous prime is 90243991829. The next prime is 90243991889. The reversal of 90243991870 is 7819934209.

It is a happy number.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 2610786 + ... + 2645125.

It is an arithmetic number, because the mean of its divisors is an integer number (5428043118).

Almost surely, 2^90243991870 is an apocalyptic number.

90243991870 is a deficient number, since it is larger than the sum of its proper divisors (83453387906).

90243991870 is a wasteful number, since it uses less digits than its factorization.

90243991870 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5256036.

The product of its (nonzero) digits is 979776, while the sum is 52.

The spelling of 90243991870 in words is "ninety billion, two hundred forty-three million, nine hundred ninety-one thousand, eight hundred seventy".