66409451 has 2 divisors, whose sum is σ = 66409452. Its totient is φ = 66409450.

The previous prime is 66409433. The next prime is 66409457. The reversal of 66409451 is 15490466.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 66409451 - 2²² = 62215147 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (66409457) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 33204725 + 33204726.

It is an arithmetic number, because the mean of its divisors is an integer number (33204726).

Almost surely, 2^66409451 is an apocalyptic number.

66409451 is a deficient number, since it is larger than the sum of its proper divisors (1).

66409451 is an equidigital number, since it uses as much as digits as its factorization.

66409451 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 25920, while the sum is 35.

The square root of 66409451 is about 8149.1994085309. The cubic root of 66409451 is about 404.9579817202.

The spelling of 66409451 in words is "sixty-six million, four hundred nine thousand, four hundred fifty-one".