6721951 has 2 divisors, whose sum is σ = 6721952. Its totient is φ = 6721950.

The previous prime is 6721943. The next prime is 6721961. The reversal of 6721951 is 1591276.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 6721951 - 2³ = 6721943 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (6721961) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 3360975 + 3360976.

It is an arithmetic number, because the mean of its divisors is an integer number (3360976).

Almost surely, 2^6721951 is an apocalyptic number.

6721951 is a deficient number, since it is larger than the sum of its proper divisors (1).

6721951 is an equidigital number, since it uses as much as digits as its factorization.

6721951 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 3780, while the sum is 31.

The square root of 6721951 is about 2592.6725593488. The cubic root of 6721951 is about 188.7260197888.

The spelling of 6721951 in words is "six million, seven hundred twenty-one thousand, nine hundred fifty-one".