6690981 has 8 divisors (see below), whose sum is σ = 9732384. Its totient is φ = 4055120.

The previous prime is 6690973. The next prime is 6690989. The reversal of 6690981 is 1890966.

6690981 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

It is an interprime number because it is at equal distance from previous prime (6690973) and next prime (6690989).

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 6690981 - 2³ = 6690973 is a prime.

It is a super-2 number, since 2×6690981² = 89538453484722, which contains 22 as substring.

6690981 is a lucky number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (6690989) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 101346 + ... + 101411.

It is an arithmetic number, because the mean of its divisors is an integer number (1216548).

Almost surely, 2^6690981 is an apocalyptic number.

It is an amenable number.

6690981 is a deficient number, since it is larger than the sum of its proper divisors (3041403).

6690981 is a wasteful number, since it uses less digits than its factorization.

6690981 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 202771.

The product of its (nonzero) digits is 23328, while the sum is 39.

The square root of 6690981 is about 2586.6930625801. The cubic root of 6690981 is about 188.4357348113.

The spelling of 6690981 in words is "six million, six hundred ninety thousand, nine hundred eighty-one".