6991775 has 12 divisors (see below), whose sum is σ = 9908592. Its totient is φ = 4794240.

The previous prime is 6991741. The next prime is 6991783. The reversal of 6991775 is 5771996.

It is not a de Polignac number, because 6991775 - 2⁶ = 6991711 is a prime.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 19802 + ... + 20151.

It is an arithmetic number, because the mean of its divisors is an integer number (825716).

Almost surely, 2^6991775 is an apocalyptic number.

6991775 is a deficient number, since it is larger than the sum of its proper divisors (2916817).

6991775 is a wasteful number, since it uses less digits than its factorization.

6991775 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 39970 (or 39965 counting only the distinct ones).

The product of its digits is 119070, while the sum is 44.

The square root of 6991775 is about 2644.1964753021. The cubic root of 6991775 is about 191.2181657752.

The spelling of 6991775 in words is "six million, nine hundred ninety-one thousand, seven hundred seventy-five".