7921457 has 2 divisors, whose sum is σ = 7921458. Its totient is φ = 7921456.

The previous prime is 7921451. The next prime is 7921489. The reversal of 7921457 is 7541297.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 7890481 + 30976 = 2809^2 + 176^2 .

It is a cyclic number.

It is not a de Polignac number, because 7921457 - 2¹⁰ = 7920433 is a prime.

It is not a weakly prime, because it can be changed into another prime (7921451) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 3960728 + 3960729.

It is an arithmetic number, because the mean of its divisors is an integer number (3960729).

Almost surely, 2^7921457 is an apocalyptic number.

It is an amenable number.

7921457 is a deficient number, since it is larger than the sum of its proper divisors (1).

7921457 is an equidigital number, since it uses as much as digits as its factorization.

7921457 is an evil number, because the sum of its binary digits is even.

The product of its digits is 17640, while the sum is 35.

The square root of 7921457 is about 2814.5083051929. The cubic root of 7921457 is about 199.3433212247.

The spelling of 7921457 in words is "seven million, nine hundred twenty-one thousand, four hundred fifty-seven".