6446478377 has 2 divisors, whose sum is σ = 6446478378. Its totient is φ = 6446478376.

The previous prime is 6446478347. The next prime is 6446478461. The reversal of 6446478377 is 7738746446.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 3982745881 + 2463732496 = 63109^2 + 49636^2 .

It is a cyclic number.

It is not a de Polignac number, because 6446478377 - 2²² = 6442284073 is a prime.

It is not a weakly prime, because it can be changed into another prime (6446478307) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 3223239188 + 3223239189.

It is an arithmetic number, because the mean of its divisors is an integer number (3223239189).

Almost surely, 2^6446478377 is an apocalyptic number.

It is an amenable number.

6446478377 is a deficient number, since it is larger than the sum of its proper divisors (1).

6446478377 is an equidigital number, since it uses as much as digits as its factorization.

6446478377 is an evil number, because the sum of its binary digits is even.

The product of its digits is 18966528, while the sum is 56.

The square root of 6446478377 is about 80289.9643604355. The cubic root of 6446478377 is about 1861.1191454430.

The spelling of 6446478377 in words is "six billion, four hundred forty-six million, four hundred seventy-eight thousand, three hundred seventy-seven".