378451906561 has 2 divisors, whose sum is σ = 378451906562. Its totient is φ = 378451906560.

The previous prime is 378451906531. The next prime is 378451906631. The reversal of 378451906561 is 165609154873.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 378078644161 + 373262400 = 614881^2 + 19320^2 .

It is an emirp because it is prime and its reverse (165609154873) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 378451906561 - 2⁵ = 378451906529 is a prime.

It is not a weakly prime, because it can be changed into another prime (378451906531) 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, 189225953280 + 189225953281.

It is an arithmetic number, because the mean of its divisors is an integer number (189225953281).

Almost surely, 2^378451906561 is an apocalyptic number.

It is an amenable number.

378451906561 is a deficient number, since it is larger than the sum of its proper divisors (1).

378451906561 is an equidigital number, since it uses as much as digits as its factorization.

378451906561 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 5443200, while the sum is 55.

The spelling of 378451906561 in words is "three hundred seventy-eight billion, four hundred fifty-one million, nine hundred six thousand, five hundred sixty-one".