6899909749 has 4 divisors (see below), whose sum is σ = 6900075936. Its totient is φ = 6899743564.

The previous prime is 6899909747. The next prime is 6899909761. The reversal of 6899909749 is 9479099986.

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 6899909749 - 2¹ = 6899909747 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 (6899909741) 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, 38352 + ... + 123574.

It is an arithmetic number, because the mean of its divisors is an integer number (1725018984).

Almost surely, 2^6899909749 is an apocalyptic number.

It is an amenable number.

6899909749 is a deficient number, since it is larger than the sum of its proper divisors (166187).

6899909749 is an equidigital number, since it uses as much as digits as its factorization.

6899909749 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 166186.

The product of its (nonzero) digits is 79361856, while the sum is 70.

The square root of 6899909749 is about 83065.6953802230. The cubic root of 6899909749 is about 1903.7699615459.

The spelling of 6899909749 in words is "six billion, eight hundred ninety-nine million, nine hundred nine thousand, seven hundred forty-nine".