669948451 has 2 divisors, whose sum is σ = 669948452. Its totient is φ = 669948450.

The previous prime is 669948449. The next prime is 669948497. The reversal of 669948451 is 154849966.

It is a happy number.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 669948451 - 2¹ = 669948449 is a prime.

Together with 669948449, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (669946451) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 334974225 + 334974226.

It is an arithmetic number, because the mean of its divisors is an integer number (334974226).

Almost surely, 2^669948451 is an apocalyptic number.

669948451 is a deficient number, since it is larger than the sum of its proper divisors (1).

669948451 is an equidigital number, since it uses as much as digits as its factorization.

669948451 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 1866240, while the sum is 52.

The square root of 669948451 is about 25883.3624361287. The cubic root of 669948451 is about 875.0115703504.

The spelling of 669948451 in words is "six hundred sixty-nine million, nine hundred forty-eight thousand, four hundred fifty-one".