6990210981 has 20 divisors (see below), whose sum is σ = 11245412332. Its totient is φ = 4301667648.

The previous prime is 6990210973. The next prime is 6990210989. The reversal of 6990210981 is 1890120996.

It is an interprime number because it is at equal distance from previous prime (6990210973) and next prime (6990210989).

It can be written as a sum of positive squares in 2 ways, for example, as 4710625956 + 2279585025 = 68634^2 + 47745^2 .

It is not a de Polignac number, because 6990210981 - 2³ = 6990210973 is a prime.

It is a super-2 number, since 2×6990210981² = 97726099117785964722, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (6990210989) by changing a digit.

It is a polite number, since it can be written in 19 ways as a sum of consecutive naturals, for example, 3318136 + ... + 3320241.

Almost surely, 2^6990210981 is an apocalyptic number.

It is an amenable number.

6990210981 is a deficient number, since it is larger than the sum of its proper divisors (4255201351).

6990210981 is a wasteful number, since it uses less digits than its factorization.

6990210981 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6638402 (or 6638393 counting only the distinct ones).

The product of its (nonzero) digits is 69984, while the sum is 45.

The square root of 6990210981 is about 83607.4816090043. The cubic root of 6990210981 is about 1912.0390658505.

The spelling of 6990210981 in words is "six billion, nine hundred ninety million, two hundred ten thousand, nine hundred eighty-one".