6991271 has 12 divisors (see below), whose sum is σ = 8269560. Its totient is φ = 5891760.

The previous prime is 6991253. The next prime is 6991277. The reversal of 6991271 is 1721996.

It is not a de Polignac number, because 6991271 - 2¹⁴ = 6974887 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 (6991277) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 1820 + ... + 4158.

It is an arithmetic number, because the mean of its divisors is an integer number (689130).

Almost surely, 2^6991271 is an apocalyptic number.

6991271 is a gapful number since it is divisible by the number (61) formed by its first and last digit.

6991271 is a deficient number, since it is larger than the sum of its proper divisors (1278289).

6991271 is a wasteful number, since it uses less digits than its factorization.

6991271 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2414 (or 2407 counting only the distinct ones).

The product of its digits is 6804, while the sum is 35.

The square root of 6991271 is about 2644.1011705304. The cubic root of 6991271 is about 191.2135710301.

The spelling of 6991271 in words is "six million, nine hundred ninety-one thousand, two hundred seventy-one".