6721501 has 2 divisors, whose sum is σ = 6721502. Its totient is φ = 6721500.

The previous prime is 6721489. The next prime is 6721523. The reversal of 6721501 is 1051276.

It is an a-pointer prime, because the next prime (6721523) can be obtained adding 6721501 to its sum of digits (22).

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 5616900 + 1104601 = 2370^2 + 1051^2 .

It is a cyclic number.

It is not a de Polignac number, because 6721501 - 2⁵ = 6721469 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (6721541) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 3360750 + 3360751.

It is an arithmetic number, because the mean of its divisors is an integer number (3360751).

Almost surely, 2^6721501 is an apocalyptic number.

It is an amenable number.

6721501 is a deficient number, since it is larger than the sum of its proper divisors (1).

6721501 is an equidigital number, since it uses as much as digits as its factorization.

6721501 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 420, while the sum is 22.

The square root of 6721501 is about 2592.5857748588. The cubic root of 6721501 is about 188.7218082831.

Adding to 6721501 its reverse (1051276), we get a palindrome (7772777).

The spelling of 6721501 in words is "six million, seven hundred twenty-one thousand, five hundred one".