1401378779 has 2 divisors, whose sum is σ = 1401378780. Its totient is φ = 1401378778.

The previous prime is 1401378773. The next prime is 1401378787. The reversal of 1401378779 is 9778731041.

It is a happy number.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 1401378779 - 2¹² = 1401374683 is a prime.

It is not a weakly prime, because it can be changed into another prime (1401378773) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 700689389 + 700689390.

It is an arithmetic number, because the mean of its divisors is an integer number (700689390).

Almost surely, 2^1401378779 is an apocalyptic number.

1401378779 is a deficient number, since it is larger than the sum of its proper divisors (1).

1401378779 is an equidigital number, since it uses as much as digits as its factorization.

1401378779 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 296352, while the sum is 47.

The square root of 1401378779 is about 37434.9940430074. The cubic root of 1401378779 is about 1119.0560655932.

The spelling of 1401378779 in words is "one billion, four hundred one million, three hundred seventy-eight thousand, seven hundred seventy-nine".