919900987 has 4 divisors (see below), whose sum is σ = 921730320. Its totient is φ = 918071656.

The previous prime is 919900973. The next prime is 919900999. The reversal of 919900987 is 789009919.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 789009919 = 929 ⋅849311.

It is a cyclic number.

It is not a de Polignac number, because 919900987 - 2⁷ = 919900859 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (919901987) by changing a digit.

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 3 ways as a sum of consecutive naturals, for example, 913912 + ... + 914917.

It is an arithmetic number, because the mean of its divisors is an integer number (230432580).

Almost surely, 2^919900987 is an apocalyptic number.

919900987 is a deficient number, since it is larger than the sum of its proper divisors (1829333).

919900987 is a wasteful number, since it uses less digits than its factorization.

919900987 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1829332.

The product of its (nonzero) digits is 367416, while the sum is 52.

The square root of 919900987 is about 30329.8695513185. The cubic root of 919900987 is about 972.5539340477.

The spelling of 919900987 in words is "nine hundred nineteen million, nine hundred thousand, nine hundred eighty-seven".