847989749 has 4 divisors (see below), whose sum is σ = 848580480. Its totient is φ = 847399020.

The previous prime is 847989739. The next prime is 847989773. The reversal of 847989749 is 947989748.

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.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-847989749 is a prime.

It is a super-2 number, since 2×847989749² = 1438173228818166002, which contains 22 as substring.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (847989719) 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, 293207 + ... + 296084.

It is an arithmetic number, because the mean of its divisors is an integer number (212145120).

Almost surely, 2^847989749 is an apocalyptic number.

It is an amenable number.

847989749 is a deficient number, since it is larger than the sum of its proper divisors (590731).

847989749 is a wasteful number, since it uses less digits than its factorization.

847989749 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 590730.

The product of its digits is 36578304, while the sum is 65.

The square root of 847989749 is about 29120.2635461975. The cubic root of 847989749 is about 946.5208842139.

Subtracting 847989749 from its reverse (947989748), we obtain a palindrome (99999999).

The spelling of 847989749 in words is "eight hundred forty-seven million, nine hundred eighty-nine thousand, seven hundred forty-nine".