996989857 has 4 divisors (see below), whose sum is σ = 997085376. Its totient is φ = 996894340.

The previous prime is 996989813. The next prime is 996989867. The reversal of 996989857 is 758989699.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also a brilliant number, because the two primes have the same length.

It is a cyclic number.

It is not a de Polignac number, because 996989857 - 2¹⁵ = 996957089 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (996989867) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 29869 + ... + 53722.

It is an arithmetic number, because the mean of its divisors is an integer number (249271344).

Almost surely, 2^996989857 is an apocalyptic number.

It is an amenable number.

996989857 is a deficient number, since it is larger than the sum of its proper divisors (95519).

996989857 is a wasteful number, since it uses less digits than its factorization.

996989857 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 95518.

The product of its digits is 88179840, while the sum is 70.

The square root of 996989857 is about 31575.1461912689. The cubic root of 996989857 is about 998.9956105396.

The spelling of 996989857 in words is "nine hundred ninety-six million, nine hundred eighty-nine thousand, eight hundred fifty-seven".