451667561 has 2 divisors, whose sum is σ = 451667562. Its totient is φ = 451667560.

The previous prime is 451667549. The next prime is 451667617. The reversal of 451667561 is 165766154.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 423577561 + 28090000 = 20581^2 + 5300^2 .

It is a cyclic number.

It is not a de Polignac number, because 451667561 - 2⁶ = 451667497 is a prime.

It is a Chen prime.

It is equal to p_23936747 and since 451667561 and 23936747 have the same sum of digits, it is a Honaker prime.

It is not a weakly prime, because it can be changed into another prime (451657561) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 225833780 + 225833781.

It is an arithmetic number, because the mean of its divisors is an integer number (225833781).

Almost surely, 2^451667561 is an apocalyptic number.

It is an amenable number.

451667561 is a deficient number, since it is larger than the sum of its proper divisors (1).

451667561 is an equidigital number, since it uses as much as digits as its factorization.

451667561 is an evil number, because the sum of its binary digits is even.

The product of its digits is 151200, while the sum is 41.

The square root of 451667561 is about 21252.4718797602. The cubic root of 451667561 is about 767.2548342483.

The spelling of 451667561 in words is "four hundred fifty-one million, six hundred sixty-seven thousand, five hundred sixty-one".