7426721 has 2 divisors, whose sum is σ = 7426722. Its totient is φ = 7426720.

The previous prime is 7426709. The next prime is 7426733. The reversal of 7426721 is 1276247.

It is a balanced prime because it is at equal distance from previous prime (7426709) and next prime (7426733).

It can be written as a sum of positive squares in only one way, i.e., 6964321 + 462400 = 2639^2 + 680^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-7426721 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (7426421) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 3713360 + 3713361.

It is an arithmetic number, because the mean of its divisors is an integer number (3713361).

Almost surely, 2^7426721 is an apocalyptic number.

It is an amenable number.

7426721 is a deficient number, since it is larger than the sum of its proper divisors (1).

7426721 is an equidigital number, since it uses as much as digits as its factorization.

7426721 is an evil number, because the sum of its binary digits is even.

The product of its digits is 4704, while the sum is 29.

The square root of 7426721 is about 2725.2010934975. The cubic root of 7426721 is about 195.1037887110.

The spelling of 7426721 in words is "seven million, four hundred twenty-six thousand, seven hundred twenty-one".