985991021 has 8 divisors (see below), whose sum is σ = 1000341120. Its totient is φ = 971687808.

The previous prime is 985991011. The next prime is 985991023. The reversal of 985991021 is 120199589.

It is a happy number.

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

It is a cyclic number.

It is not a de Polignac number, because 985991021 - 2¹⁴ = 985974637 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (985991023) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 31805 + ... + 54621.

It is an arithmetic number, because the mean of its divisors is an integer number (125042640).

Almost surely, 2^985991021 is an apocalyptic number.

It is an amenable number.

985991021 is a deficient number, since it is larger than the sum of its proper divisors (14350099).

985991021 is a wasteful number, since it uses less digits than its factorization.

985991021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 23443.

The product of its (nonzero) digits is 58320, while the sum is 44.

The square root of 985991021 is about 31400.4939610828. The cubic root of 985991021 is about 995.3083633017.

The spelling of 985991021 in words is "nine hundred eighty-five million, nine hundred ninety-one thousand, twenty-one".