285690921 has 8 divisors (see below), whose sum is σ = 387377760. Its totient is φ = 187232352.

The previous prime is 285690907. The next prime is 285690931. The reversal of 285690921 is 129096582.

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

It is not a de Polignac number, because 285690921 - 2⁶ = 285690857 is a prime.

It is not an unprimeable number, because it can be changed into a prime (285690901) 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, 806860 + ... + 807213.

It is an arithmetic number, because the mean of its divisors is an integer number (48422220).

Almost surely, 2^285690921 is an apocalyptic number.

It is an amenable number.

285690921 is a deficient number, since it is larger than the sum of its proper divisors (101686839).

285690921 is a wasteful number, since it uses less digits than its factorization.

285690921 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1614135.

The product of its (nonzero) digits is 77760, while the sum is 42.

The square root of 285690921 is about 16902.3939428709. The cubic root of 285690921 is about 658.6158019312.

The spelling of 285690921 in words is "two hundred eighty-five million, six hundred ninety thousand, nine hundred twenty-one".