400778869277 has 4 divisors (see below), whose sum is σ = 400845086940. Its totient is φ = 400712651616.

The previous prime is 400778869237. The next prime is 400778869291. The reversal of 400778869277 is 772968877004.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 193238488921 + 207540380356 = 439589^2 + 455566^2 .

It is a cyclic number.

It is not a de Polignac number, because 400778869277 - 2²⁰ = 400777820701 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (400778869237) 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 in 3 ways as a sum of consecutive naturals, for example, 33099752 + ... + 33111857.

It is an arithmetic number, because the mean of its divisors is an integer number (100211271735).

Almost surely, 2^400778869277 is an apocalyptic number.

It is an amenable number.

400778869277 is a deficient number, since it is larger than the sum of its proper divisors (66217663).

400778869277 is an equidigital number, since it uses as much as digits as its factorization.

400778869277 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 66217662.

The product of its (nonzero) digits is 66382848, while the sum is 65.

The spelling of 400778869277 in words is "four hundred billion, seven hundred seventy-eight million, eight hundred sixty-nine thousand, two hundred seventy-seven".