993904985 has 16 divisors (see below), whose sum is σ = 1229597712. Its totient is φ = 770764800.

The previous prime is 993904913. The next prime is 993904993. The reversal of 993904985 is 589409399.

It can be written as a sum of positive squares in 8 ways, for example, as 24641296 + 969263689 = 4964^2 + 31133^2 .

It is not a de Polignac number, because 993904985 - 2¹⁶ = 993839449 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 993904985.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 16745 + ... + 47625.

It is an arithmetic number, because the mean of its divisors is an integer number (76849857).

Almost surely, 2^993904985 is an apocalyptic number.

It is an amenable number.

993904985 is a deficient number, since it is larger than the sum of its proper divisors (235692727).

993904985 is a wasteful number, since it uses less digits than its factorization.

993904985 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 31084.

The product of its (nonzero) digits is 3149280, while the sum is 56.

The square root of 993904985 is about 31526.2586584580. The cubic root of 993904985 is about 997.9641866097.

The spelling of 993904985 in words is "nine hundred ninety-three million, nine hundred four thousand, nine hundred eighty-five".