6990624 has 144 divisors (see below), whose sum is σ = 22014720. Its totient is φ = 2177280.

The previous prime is 6990619. The next prime is 6990629. The reversal of 6990624 is 4260996.

It is an interprime number because it is at equal distance from previous prime (6990619) and next prime (6990629).

It is a tau number, because it is divible by the number of its divisors (144).

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (6990629) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 225489 + ... + 225519.

It is an arithmetic number, because the mean of its divisors is an integer number (152880).

Almost surely, 2^6990624 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 6990624, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (11007360).

6990624 is an abundant number, since it is smaller than the sum of its proper divisors (15024096).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

6990624 is a wasteful number, since it uses less digits than its factorization.

6990624 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 85 (or 65 counting only the distinct ones).

The product of its (nonzero) digits is 23328, while the sum is 36.

The square root of 6990624 is about 2643.9788198849. The cubic root of 6990624 is about 191.2076722936.

The spelling of 6990624 in words is "six million, nine hundred ninety thousand, six hundred twenty-four".