6890721 has 4 divisors (see below), whose sum is σ = 9187632. Its totient is φ = 4593812.

The previous prime is 6890713. The next prime is 6890753. The reversal of 6890721 is 1270986.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 6890721 - 2³ = 6890713 is a prime.

It is a d-powerful number, because it can be written as 6 + 8⁷ + 9⁷ + 0 + 7⁴ + 2¹³ + 1 .

It is a D-number.

It is not an unprimeable number, because it can be changed into a prime (6890701) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1148451 + ... + 1148456.

It is an arithmetic number, because the mean of its divisors is an integer number (2296908).

Almost surely, 2^6890721 is an apocalyptic number.

It is an amenable number.

6890721 is a deficient number, since it is larger than the sum of its proper divisors (2296911).

6890721 is a wasteful number, since it uses less digits than its factorization.

6890721 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2296910.

The product of its (nonzero) digits is 6048, while the sum is 33.

The square root of 6890721 is about 2625.0182856506. The cubic root of 6890721 is about 190.2924489837.

The spelling of 6890721 in words is "six million, eight hundred ninety thousand, seven hundred twenty-one".