6921406 has 8 divisors (see below), whose sum is σ = 10393344. Its totient is φ = 3456960.

The previous prime is 6921403. The next prime is 6921437. The reversal of 6921406 is 6041296.

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

It is a super-2 number, since 2×6921406² = 95811722033672, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (6921403) 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, 2286 + ... + 4366.

It is an arithmetic number, because the mean of its divisors is an integer number (1299168).

Almost surely, 2^6921406 is an apocalyptic number.

6921406 is a deficient number, since it is larger than the sum of its proper divisors (3471938).

6921406 is a wasteful number, since it uses less digits than its factorization.

6921406 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3746.

The product of its (nonzero) digits is 2592, while the sum is 28.

The square root of 6921406 is about 2630.8565145215. The cubic root of 6921406 is about 190.5744938667.

The spelling of 6921406 in words is "six million, nine hundred twenty-one thousand, four hundred six".