6685319621 has 16 divisors (see below), whose sum is σ = 6924579840. Its totient is φ = 6450362880.

The previous prime is 6685319593. The next prime is 6685319681. The reversal of 6685319621 is 1269135866.

It is a happy number.

It is a cyclic number.

It is not a de Polignac number, because 6685319621 - 2¹⁰ = 6685318597 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (47).

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (6685319681) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 3938645 + ... + 3940341.

It is an arithmetic number, because the mean of its divisors is an integer number (432786240).

Almost surely, 2^6685319621 is an apocalyptic number.

It is an amenable number.

6685319621 is a deficient number, since it is larger than the sum of its proper divisors (239260219).

6685319621 is a wasteful number, since it uses less digits than its factorization.

6685319621 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2884.

The product of its digits is 466560, while the sum is 47.

The square root of 6685319621 is about 81763.8038559851. The cubic root of 6685319621 is about 1883.8257334232.

The spelling of 6685319621 in words is "six billion, six hundred eighty-five million, three hundred nineteen thousand, six hundred twenty-one".